What are some good games to play on windows? I was running ubuntu previously (Still am, actually, just with a virtual box for XP). RAM isn't an issue, processor speed isn't an issue, and video isn't an issue.

WoW is out of the question. RPGs are hate. I have a Stand Alone version of Garry's Mod that doesn't want to initialize. I have starcraft, as well.

What are some good games?