you should wait for the dx11 cards that come out the end off this year. I have a 4870 OC 1 gb and can play all my games on maximum even far cry 2 [don't have crysis]
Windows 7 is indeed very nice, have been using it for half a year now and i must say it's a lot better than xp [even if it uses 30% of my ram all the time]
i had a pc childhood starting with: snoopy [some dog] commander keen Jazz Jack rabbit [super game] doom [at the age of 7 ] Dungeon keeper 2 [best game ever] Unreal Tournament [second best game] Half-life [third best game ever ] Unreal tournament 2004 Half life 2 garrymod l4d [im still a child ]