I will usually always go for non-human, sneaky, female characters.
IRL, I’m human, loud and clumsy, and male.
I generally play the lawful, good class and am the dwarf warrior. But a Paladin gives you magic too.
- I usually play female
- I feel most comfortably playing a bard, or bard-type character. They’re not as useless as people say!
- I can’t bring myself to being really evil.
- I’m a compulsive hoarder.
- I need to finish every quest/visit every map
- I try to play (semi) realistically, i.e. no resting in a middle of dungeon, no mini-maxing etc. Sometimes this conflicts with 5)
- I download tons of mods
- Including nude mods if available
- and “no XP cap” mods even thought I’m usually nowhere near the limit.
I always play a male character, usually thin, tall and wiry with pale blonde (ice blonde) features and high cheek bones (all the things I’m not, save the male part ;))…an elf if there are elves in the game (sometimes I play a dwarf, in which case I choose fire red hair and great flowing beards…again, everything I’m not save the short and fat part). I like ranged characters and stealth characters, so in D&D type games I play archer/rogues a lot, or Hunters/Engineers in MMO’s…or, in Fallout 3/NV I played a small weapons specialist who uses a lot of sniper type weapons and likes to kill from stealth. I also obsess about finding every nook and cranny on the map (in both Fallout 3 and NV my primary task was to find and explore every single point of interest, find every bobble head or snow globe, and every single named or special weapon…in fact, I STILL haven’t finished NV yet, though I’ve nearly finished exploring every interesting spot and finding ever snow globe and named/special weapon or armor set). I’m also a horder who LOVED looking at my piles of treasure and sorting out my weapons in these chests (by grade, bonus, classification, etc), armor in these, interesting items in these, etc etc…in Fallout 3 I probably spent as much time setting up my personal vault and arranging my armor on the manikins and wall of weapons and such as I did actually playing the game.
I usually play a ‘nice’ character in RPG’s and MMO’s, especially the first time through, though that wasn’t always the case. In the old pen and paper days I almost always played a chaotic evil character, and in the early MMO days I was a huge PKer…when I sold my UO account on eBay I actually had people bidding on the character just for the privilege of deleting him and getting all their stuff back, and I still remember the flames I got in that auction. My younger brother and I were probably some of the most feared and hated people on the server. I’ve mellowed considerably, however, and now my characters are almost always disgustingly nice…my Fallout 3 and NV characters are both Saviors of the Wasteland or Messiahs. 
-XT
Sadly I think the only thing I consistently do in CRPGs is “give up before the end.” I’ve only ever finished one game (an early version of NetHack). Mainly I play a game for a while, like it a lot, but for some reason wander away from it then don’t feel like picking up the same character again, so I roll a new one. I am determined to finish Oblivion before Skyrim comes out though (four months to the day away!)
If I’m in a single-player game, I’m going to have one of four names: my first name, Duke (male), Fiona, or A’Mhonadh (female). In a MMORPG I’ll try to take something original so it can be remembered.
I generally play good guys for a lot of the reasons already mentioned: it doesn’t feel right not to, playing evil is not usually fleshed out as well as playing good, etc.
I don’t like companions as a rule. I feel like I spend more time making sure they’re not dead than advancing my character. On NetHack I leave my dog/cat behind on level 1.
And, honestly, that’s about it. I’ve played male characters, female characters, magic users, hack-and-slashers, dwarf paladins, troll priests, a character whose battle cries were all in French, a character designed to look like one of our cats, you name it. Some games I hoard in, some I don’t (especially in NetHack clones where you can only carry 52 items). Sometimes I look at spoilers, sometimes I don’t.
On naming conventions: I normally name my character something vaguely plausible but silly; something like “Mergatroyd” or “Humperdinck”. Though TBH the only CRPG characters whose names I can remember are my party from Ultima III, where the two front-line characters were named “Name” and “Name” because I hit “create” before typing in a name for them.
On the subject of names, I’ve thought for a while now that “Drosophila” would make a good name for an evil sorceress or witch, and “Melanogaster” would be a good name for the aged wizard who’s her arch-nemesis.
Video game RPGs: Stalwart hero of the land who just happens to obsessively collect anything of value and hack any consoles that come into his (always his) field of vision. Seems like that’s a common RPG playing style amongst Dopers 
My typical style in pen and paper RPGs is that my character always ends up roleplaying as well. For example, my first ever character, a D&D 3.5 Halfling Rogue, spent a fair amount of time pretending to be a Paladin in order to gain favour with a church we needed intel from (the Druid was my mount, Wildshaped into a bear). My 4th Ed Ranger multi-classed into Druid solely for the Wild Shape talent, which was fairly useless in combat as I was statted for ranged combat. In Ars Magica I played a mage of House Bjornaer, whose defining characteristic is shapeshifting, and in a Dark Heresy campaign I ended up having to pretend to be my own father in order to avoid being killed for obtaining unsanctioned Psyker powers.
My current character in WFRP is a Charlatan Halfling with a fake medical degree and an array of coloured sands she sells as medicines. She’s also my first female character, but that’s because I chose her sex by flipping a coin (I love random character generation in Warhammer games).
You end up with parties that are so useless that way 
The group I started the Imperial Campaign with included a Dwarf Miner, a Halfling Ratcatcher, a Human Graverobber and a Human Student. Not one combat guy among us all (I think the best CC in the ragtag bunch was somewhere around 35%). We got creamed in the first encounter :p.
Then the DM thankfully let us roll less random characters, except for the Grave Robber who’d grown attached to his. He later went on to become the party’s doctor, but for some reason we were never quite comfortable letting him operate on us :D.
If we’re including pen-and-paper, one constant among my characters is the multi-page equipment list. By second level, I’ve usually got at least one of everything nonmagical from the books, plus several things that aren’t in the books (you’d be amazed how often a few cockleburrs come in handy, for instance). This is, of course, a reflection of my real-life self: Whenever anyone asks “Hey, does anyone have a…”, I pride myself on always being able to answer “yes”, usually with something I have on my person.
The only thing I don’t get for my characters is the ten-foot pole. I really did buy a couple of ten-foot poles in real life once, and it’s a lot more awkward than most folks realize to carry those things around.
I am fussy about class, but it always follows the same basic formula:
In 3rd person perspective RPGs (single-player), I will always play a caster, but generally not a pure DPS caster. Fireball mage? No thanks. Warlock? Druid? Summoner? Hell yes.
1st person RPG: thieves. I enjoy the stealth aspect but I just can’t be arsed if it’s not real-feeling. My favorite are ranged combat thieves (e.g. archers, snipers). I will max stealth and theft-related skills first. But, I generally don’t enjoy melee rogue combat, so if there’s a stealthy caster instead, I’ll go there. Or for pure skill-based games, I’ll pick stealth and then caster abilities. I just can’t not take stealth.
Related, I suppose, is theft. I will steal everything that is not nailed down. There doesn’t need to be a lot of gain in this. In Morrowind I cleared whole towns of their dishes and cutlery. There does, though, have to be some element of risk, or it’s no fun.
I am also a collector. I tend not to hoard everything, but I like to collect all of the weapons and armor. I establish a den and just fill up everything. In Morrowind I had piles upon piles of glass armor and daedric weapons, books, potions, materials… all carefully arranged. In Fallout 3 and New Vegas, I kept practically every crafting material I found, one of every weapon and armor (max repaired as possible), all ammo – anything I could figure. All were sorted into containers by type. I don’t even get this because I can’t organize shit in real life at all. My house is cluttered and disorganized, but yet I’d happily spend hours meticulously organizing virtual garbage.
I tend to play good players or cartoonishly evil ones. It’s rare that I play someone middle ground. Often I’ll go back and play it through as the other alignment and it’s very rare that a neutral perspective gains you any unusual content the way that the extremes do. However, my perspective on evil is a little different than the game often expects. This doesn’t mean that I blindly ally with the bad guys. If saving the town is the better reward, then the bad guy can go fuck himself. If someone has something I want, I take it – however good or evil they might be is of no particular concern to me. I’m in it for the caps, bitches!
I almost always choose extremes in physical appearance. For example, making all physical attributes extreme in one direction – very tall, very short, very fat, very thin, that sort of thing. In games with pre-set races, this generally means I always play males (female features are almost always very muted and samey). Draenei, Tauren, gnomes, dwarves, hobbits? Yes please! Humans, elves, stuff that looks like humans, anything intended to be sexy looking? Zzzzzz.
I almost always…
Play a melee specialist first.
Skip flavor text if possible.
Look up [game name]&" tips" and/or [game name]&" strategy" fairly early in the game to get some pointers, but I try to avoid major spoilers. I haven’t read a full walkthrough in a long time but if I get stuck I’ll look up the solution.
Regret looking up the solution when I see how simple it was.
Name my first character “Able”.
Abandon my first character.
Focus on tactics and fighting enemies over exploration or story.
I very rarely…
Try to “complete” the game by doing all the side quests, revisiting areas, etc.
Play an elf or dwarf, except in Dungeon Crawl Stone Soup.
Play a female.
Care what my character looks like. Sure, I’ll wear that silly hat if it gives a damage bonus. Hope it goes with my Rainbow Suspenders of the Munchkin…
I started with a graverobber but she got accidentally shot in the neck by one of the Elves in our party. Her sister was then recruited, who sold the body to the local doctor (she died the way she lived).
Our current problem is too much muscle - we’ve got an Outlaw/Pit Fighter, Militiaman and Marine in addition to my Charlatan. We’re trying to replace the two (almost identical) Elven Medical Students who left the campaign as they moved away, so that we can have alternative plans to “run in and melee everything to death”.
Back on topic: I also don’t like companions in video game RPGs. I don’t like organising them, I don’t like them getting in the way, and they’re only useful for drawing fire. I did once get a nice magical necklace off the body of a botched escort mission subject in Oblivion, though.
I once had someone tell me that he didn’t like using a particular piece of equipment because he didn’t like how it looked… He said this while wearing a bright green skull helmet as a paladin.
I do this!
I’m an anti-hoarder–I ruthlessly toss/sell/disenchant/disassemble anything that seems like it’ll have no further use. I do hoard consumables/ingredients, though.
My second playthrough is always a woman.
I am prone to the snarky do-gooder as well, one of the reasons I dig Mass Effect so much is that the morality system lets me max Paragon while still having a significant quantity of Renegade to show I mean business.
I’m always a technical heavy fighter–for examples, in Dragon Age I did 2-Handed Sword warrior, in Mass Effect I am an Infiltrator (soldier/engineer hybrid with lots of debuffs and a sniper rifle).
I always play the romance plots, and I always pick the most unconventional hetero pairing I can (on my female playthroughs, I tend to pick the guy most like my first character).
I go for completionism/100%s as much as I can. I absolutely adore games that have an exploration bonus. On the other hand, I refuse to participate in game features that can only be fully unlocked with multiple playthroughs (I have never once unlocked a companion achievement in Mass Effect, because it’s not possible to get any more than two of the six in any given playthrough.)
I prefer having one character and playing out all the nifty bits at endgame to generating new characters. I will load up old uber-powerful characters and just wander around the world in games that let you do that in a post-end-boss save.
Oh yes, I also pick items for aesthetics rather than utility (LOTRO almost won me over just for the ability to wear a cosmetic gear set over your stat set).
I get very annoyed and often will abandon-before-completion any game that doesn’t let me have a decent full beard as a male character (Mass Effect’s stubble just BARELY counts).
I always use the same names: Zeriel and Meholick for males, Ekaterina and Seraphina for females.
I tend toward thieves or characters with thief abilities with playing. It’s more fun to me to hide and stab and steal than to just dice roll for the biggest Hulk Smash.
Walkthroughs? Strategy guides? CHEATS?!? Blasphemy! These are clearly tools of the Dark Lord, to make us weak when the true threat comes. I’ll take my chances with Guide Dang It, thank you very much.
I still play text-based MUDs. In fact, just the one, the Wheel of Time MUD(http//wotmud.com, go on, you know you want to). I’ve never played EverQuest or WoW (I know, I’m a Luddite) but I’m not opposed to them. When I have a system and time to devote, I’ll check them out. But a text-based MUD… it’s reading, and it’s an RPG. Yeah!
Where I have multiple members of a party, at least one must be named ‘Max Axe’.