I’m not touching the ATIvs Nvidia flame war other than to say I <3 Nvidia and that chart about crashes in Vista is likely because there is more Nvidia cards out there.
I will say that for games the Core 2 E8400 is likely to be much better and cheaper than the Q9300. Depends on what other apps you run and how multi-threaded they are.
Also, do you have any dreams of overclocking one day?