The ring was left in Barad-dur before Sauron surrendered to the Numenoreans.
He had the ring with him when he drowned. Then his spirit, um, spirited it back to M-E.
http://www.daimi.au.dk/~bouvin/tolkien/ringnumenordestroyed.html
I guess he was less feeble after his first death than he was after his second death. Or maybe the fact that Isildur actually snatched the ring away after the second death made it harder for Sauron to regain his senses/keep track of the ring.
Tolkien muffs this, IMO, but what can you do?
Yeah, that seems a bit weak to me. I mean, if he could levitate a ring, why couldn’t he levitate himself while wearing the ring, and keep from drowning?
As you say, the results of him being killed and being physically separated from the ring seem to be very different the first time it happened than the second time. But that could because someone else (Islildur) actually had possession of the ring the second time.
OK, GonzoGal asked me one that I think I should know, but can’t recall.
If Moria was a dwarven city, why was “speak friend and enter” written in elvish, and why was the password “mellon” and not the dwarvish word for friend?
I’m thinking maybe the door was made in a time when elves and dwarves were friendlier, or something?
Because the dwarves of Khazad-dum and the elves of Hollin (the land those gates faced) were on extremely friendly terms when the gates were made. In fact, the inscription on the door was made by an elf. Most people coming to that door in the good old days would probably have been elves.
The antagonism between dwarves and elves was, IIRC, connected to the fall of Moria. The elves didn’t think too highly of the dwarves mucking about and awakening a Balrog.
The western door of Moria faced Eregion, an elvish land where the Noldor forged the rings of power. There was great commerce and friendship between the two lands. That and an elf was involved with the crafting of the doors.
As to Sauron’s ring, I though the Silmarillion stated that he returned to Mordor and took his ring back up. Apparently I need to invest in the HOME volumes. 
Quoth Ludovic, in reference to human and non-human DNA:
My take on that is that Melian is an Ainu, and therefore took part in the Creation of the whole world. I think of her part of the parentage of Luthien as a sort of special act of sub-creation, rather than the conventional mixing of DNA. Of course, once Luthien existed, she was a creature in the normal physical sense, with cells and genes and the like, so the lineage past there would have been normal.
As for Elves, I suspect that human biology would class them as a subspecies of Homo sapiens, despite the significant differences between elves and humans. But then, modern human biology is really rather ill-equipped to describe Elves (or Dwarves, or Orcs, or Fell-Beasts, for that matter).
Is there a Tolkien encyclopedia out there? I think I need one!
Also, what’s up with this line:
So basically, Denethor loves Boromir more because he and Faramir are too much alike?
Also, how long has Gondor been without a King and under a steward?
Eärnur, the last king of Gondor, was killed by the Witch-King in a duel in 2050. So the Stewards ruled 971 years until Aragorn Elessar was crowned king.
It goes further back than that. Even before the sun and moon rose, the elves and dwarves were in conflict. When the dwarves showed up, the elves thought they were particularly short orcs and made war on some of them.
Then that whole mess with the Nauglamir back in Doriath didn’t help much either. Thingol getting offed by the dwarves of Belegost (the Broadbeams) long tainted relations after. Even though the dwarves of Nogrod (the Firebeards) tried to dissuade the Belegosians from their plan, and stood aside, the Nogrodniks bore the brunt of elvish hostility for long.
But Durin’s line (the Longbeards) has been most consistantly friendly towards (or at least not overtly hostile to) the elves.
As others have stated, you are basically correct. Moria itself is an Elvish name (Dwarves called it Khazad-dum). Several places in LOTR are referred to by different names depending on the language used e.g. Rivendell/Imladris, Isengard/Orthanc. Rohan is the name bestowed on that land by Gondorians. The people that live there (the Rohirrim) call it The Mark in their own tongue. Quite a bit of this has carried over to the movies, so I wonder how confusing it is to someone who was never read the books.
More confusingly, Moria was never called that until the Dwarves woke the Balrog. Before that, there were several names (of course!). The Dwarves called it Khazad-dûm (Dwarf-Mansions), the Elves called it Hadhodrond (Dwarf-Cavern), and in untranslated Westron it was Phurunargian (Dwarf-Delve, translated as “Dwarrowdelf”).
Only after Durin’s Bane was awoken to stalk its halls in TA 1980 was it called Moria (The Dark Cavern).
Tolkien makes it clear in various places (perhaps Dr Mercotan may be of assistance in refreshing my memory as to exactly where) that the Valar and Maiar were spirits who could at will take on fanar (sing., fana), bodies that would function exactly as those of Men, Dwarves, and especially Elves, but which were worn as “garment” rather than being the permanent dwelling of the Maia or Vala who inhabited them. We have several cases of this happening in the Hobbit, LOTR and Silmarillion: Curumo, who became Saruman; Olorin, who became Gandalf; Aiwendil, who became Radagast; Melian; Morgoth; Sauron himself in the Second Age; Aulë; and IIRC Yavanna when she dealt with the dying Trees.
From the encyclopedia (linked by JJ)
I am, sadly, away from home and my sources, but at the West Gate Gandalf says (from my memory)
I thought that Orthanc was the name of the tower itself, while the area around it was called Isengard.
The names have meaning. Isengard is (in Westron/Common Speech) the fortress that guards the Isen (Iron) River, in Sindarin Angrenost, with the same meaning. Orthanc means something like forked tower. However, in Sindarin the coined word “orthanc” means “cunning mind” and was adopted as the name for the tower in reference to Saruman, in a bilingual pun.
/Mor-/ likewise has the meaning of (the color) black, with the evil connotation of the term sometimes meant and sometimes not. Although “Mordor” was the black land, with Sauron’s evil intended, “Moria” simply means “the Black Pit” with reference to its being underground and unlighted, and “Morthond,” the name of a river in Gondor, is simply “Blackroot” with reference to its rising in an area of black rock, and no evil meaning included.
The River Brandywine is a Hobbitish pun on its Sindarin name, Baranduin, which means “Golden Brown River.” There are a lot of color/direction names in Sindarin with connotations sometimes meant and sometimes not.
Okay, why did Galadriel have to be tested by the Ring? And then why did she know she had to leave?
Because now Middle Earth would change, because the Rings would no longer preserve everthing?
And what about the Nazghul? When the One was destroyed, were they free?
Who were the other two Istari? was their purpose to help the people of middle-earth too? If so then why is Radagast so worthless? He has such a short part in the books he could’ve been played by Gary Coleman in the movies. What happened to radagast afterwards?
Galadriel had to test herself against the temptation of the ring to pass her “test” – in effect to earn herself the right to return to the West. By the curse of the Noldor, she was confined to middle earth. In this sense, she didn’t have to leave, but there would be nothing left in Middle Earth for her after the ring is destroyed, so she wanted to. By rejecting the temptation of the ring, she “cleanses” herself of the curse of the Noldor and her involvement in the kinslaying, and earns passage on the last ship.
As for the other two Istari, they don’t have names that i know of (other than the blue wizards) and they went into the east and became corrupted. Originally they were supposed to help the people of middle earth (all 5 of the istari were supposed to). I think that Radagast and the blue wizards were perhaps just less powerful, or maybe a more correct statement is that their power was in different areas - Radagast with birds and beasts and nature, who knows what the blue wizards were good at. Also, remember that Gandalf held one of the Three elven rings, which made him a little stronger.
According to the Essay on the Istari in Unfinished Tales, the leaders of the Wizards (implying there were more) were five:
Saruman and Gandalf (enough said about each)
Radagast, who was a Maia named Aiwendil, of the people of Yavanna, enamored of the plants and animals (Aiwendil means bird-lover). Apparently his fault was that he got preoccupied with his interest in Middle-Earth wildlife to the exclusion of his duty to combat Sauron, instead of using his lore to aid in the fight. (E.g., with Radagast doing his job, the “Fenris Eagle scenario” discussed in another thread might have been a possibility; with his using his Maia powers, he could have tamed and turned the Mumakil to the side of good.)
The other two Wizards were Alatar and Pallando, the Blue Wizards, who went with Curunir (Saruman) into the East beyond the Sea of Rhun, and did not return with him, or at all. Nothing is known (per Tolkien) of what they did there, whether they stayed true to Eru and the Valar, whether they survived, etc.