Vista 64, Vista or XP

Case - Cooler Master RC690
Mobo - Gigabyte P35-DS3P
Video Card - EVGA 640 8800GTS
CPU - Intel Q6600
Hard Drives - 4 Seagates 160gig (I plan on running 1 Raid 0 and 1 Raid 1)
Power Supply - Corsair 620W
RAM - Crucial Ballistic PC2 6400 2x1gb (2 sets for 4gb) - could drop to 2gb for regular Vista
Some keyboard not sure yet
A floppy drive - need this to load stinking Raid drivers (one would think they could figure out a different way)
DVD - Ripping out BenQ from old computer
CPU Heatsink - Zalmann CNPS9500 92mm
Case Fans - 2 Scythe Minebea Silent IC Series 120mm
Speakers - Logitech Z4 (I am not an audiophile, but I would like a decent set of speaks since my old pair stopped working on my current computer this week)

Undecided about O/S, either XP or Vista. Too many varying opinions on what works and what doesn't with Vista, drives me up the wall just reading all of the opinions. I upgrade my computer about once every five to six years.

This computer will be used for some gaming (Crysis and CD4), I do quite a bit of home movie capturing and encoding to mpeg2, photo editing and the typical get on the internet and goof off.

Will most software work in a 64 bit system? I have no experience with a 64 bit system, but figured if I was going to purchase 4gb of ram I might want to purchase a 64 o/s.

Crysis definitely takes good advantage of DX-10...
DX-10 is only on Vista
32 Bit Vista has less compatibility issues than 64 bit

So 32 bit Vista for now, for sure. If you buy a regular licence, you can install both 32 and 64 in a Dual boot system should you be undecided. I'm running 32 bit ATM, but will go dual boot when I can get one of the new Seagate 7200.11 drives