Yep, that’s my pick.
Or you can pick up Titan Quest and its expansion, Immortal Throne, from Steam. A rather under-rated Diablo-clone.
Civilization 5 is coming out in a week (or so) and I think could be played co-op (you and your gf need to agree to work together of course).
I have not tried the new one but am a huge fan of the series. You might have fun with that.
Turn based though so the pace is slower.
Thirding (or whatever) Titan Quest if the both of you liked Diablo II and want more of the same (albeit with better graphics and more interesting character classes). Give the demo a spin, you’ll probably like it. Does *Torchlight *have co-op ? I also heard good things about it.
Mount & Blade is extremely good, but alas, poor Yorick, no co-op. There is multiplayer however. Demo here.
Somewhat niche, but you might want to check out Blood Bowl. On the surface it looks like a sports game, but in reality it’s an odd mix of chess-like strategy, bit of luck, bit of RPG, tons of fun and opportunities for cheap shots. Sadly, no demo.
You may also want to check out Heroes of Might & Magic V - the campaign is single player only, but single maps as well as user-made maps & campaigns can be played multi, either co-op or against each other. It’s a mix of turn-based strategy, empire management and a smidge of RPG on top. Certainly no action fest though. Demo here.
There was an unofficial hack for co-op, but Torchlight II will have multi-player mode.
Also, if you don’t mind platforming, Trine has a wicked co-op mode which is loads of fun for 2 players.
She played Torchlight extensively for 2-3 months and loved it, but we were saddened when we noticed that it didn’t have co-op. We’ve been waiting for TL2 for that very reason.
I’ll have to check out some of these titles. Seems that most votes seem to be for ‘Borderlands’ with ‘Titan Quest’ being a close second. I only played TQ for a day or so (unable to play with friends as my one buddy lagged too hard during gameplay and would crash our server). It had an interesting feel to it.
For anyone that’s played DAoC, I’m surprised it wasn’t mentioned as being evil towards casual players. It is the epitome of that. Competition in RvR (the game’s PvP equivalent) is rough and unforgiving if you don’t know what you’re doing. The game has been made infinitely easier through patches, but the PvE years ago used to be hilariously difficult. I’ve played for years and years (only casually now since my characters are established), and it’s harsh for new players, even still.
That would be Mount & Blade: Warband, which does not require the original to play.
I see Unreal Tournament 3 has a co-op mode. I had that when Steam was running a free weekend for it a while back. Nice game.