Please recommend self-contained PC RPGS

Neverwinter Nights, and Morrowind.

I third the nomination for Morrowind. Buy one of the two expansion packs too - it comes with a fix to the journal UI that makes the game much easier to play. If you're willing to go for older games, Baldur's Gate 2 and Planescape: Torment have some of the best writing of any computer game either. If you're not wedded to the fanatasy thing, Star Wars: Knights of the Old Republic is also awesome.

I second the Fallout series. Fallout 2 monopolized my summer when it was released.

I'm playing through Fallout 2 right now and it's an amazing game. Sure the technology is dated, but the story is good, the world is very open-ended, and the scope is huge. That, and the BG series can all be gotten cheap these days.

Gothic is old, but fairly good. Not terribly challenging, but fun nonetheless. (Note: I rarely play RPGs.)

How many of the classics have you played? The single-player RPG is pretty much dead in any interesting form, ending more or less with the Fallout series (don't talk to me about Baldur's Gate; I hold it in low esteem). Since just about all you can get today are uninspiring Japanese-style RPGs, classics are where some of the best stories and play are to be found. The Bard's Tale series is highly worthwhile, as is the functionally similar but slightly more up-to-date Might and Magic (pre-"Heroes of"), especially the later parts of the series. My favorite of the classics, which has both excellent gameplay and a well-crafted story, is http://www.legacyoftheancients.com/, but you'll need to bust out a C64 emulator to play the good version. It's well worth the hassle. If you're willing to depart from fantasy genre, there is pretty much no better RPG than Wasteland, although Mars Saga is alright. You might not get the flashy graphics or real-time combat in the old school classics, but you generally get a better game.

Either majick has not played Morrowind, or is wrong. The Morrowind game of the year edition is 1) a steal, and 2) awesome.

I thought Wasteland and its sequels (the 2 fallout games) were absolutely fantastic. I wish they made a third one in the fallout series. And I wish Morrowind and some of these other games would run on a Mac. There don't seem to be any good, open-ended and large-world Mac scifi games out there.

Thank you everybody for your suggestions! I went and bought Morrowind's Anniversary Edition, and next time I have free money, I'm going to try some of the others listed here. (As a note, the graphics don't have to be flashy, but I do like pretty spell effects, and older games are fantastic because they're more affordable.)