Well, I finally fixed the problem! Well, sorta.
I just updated my computers to windows 7 ultimate x64. My macbook pro uses the 197.16 drivers and everything works fine. It hasn't crashed on my desktop either (also running windows 7 ultimate x64 now). I've played it for about 2 hours so far straight with no crashes!
It has been a frustrating week, but I can now finally enjoy this game. It's pretty awesome!
Thanks to everyone who helped!!!