Good pc games?

[BumblebeeCody]

Galactic Warfare is godlike! Can't go wrong with Team Fortress 2. It's free (with no additional charge rubbish)

Tribes Ascend is free and pretty good, but one of those "micro-transactions games".

World of Warcraft is a great MMORPG and it's free to play (up to Level 20). Though I'd also say that if you haven't played an MMORPG before, wait till Tera Online comes out.

Minecraft and Audiosurf are good for killing time

A good single player I highly recommend is Witcher 2. Story is mature with well developed characters and a decent plot. Much better than Skyrim (not that Skyrim is bad).

If you want a decent fighting game get Super Street Fighter 4 Arcade Edition. Amazing fighting game (though AE is a tad disappointing)

2 good puzzle games I'd recommend are Portal(and Portal 2) and Quantum Conundrum(newly released)