32 or 64 bit

x64 is (in theory) safer because it has PatchGuard that stops unwanted modification of the Windows Kernel.
But still anyone having less than 2gb of ram shouldn't use it.

mcleod55 said:

Would 64 run OK with just 4 gb RAM? I have 4 installed ddr2 800 and I have an extra 2 gb RAM but it's ddr2 667. That would give me 6 gb but it would downgrade the 800 ram. It wouldn't help, would it? If it will run OK with 4 gb for now, then I could get another 4 to match later.

I have reviewed your sys specs and you have more than adequate horse power to run OS_7 in 64 bit. My system is almost identical except for memory where I use DDR3 but you have a strong processor, 4 gigs of memory and more than adequate storage.
IMHO older legacy hardware such as printers/scanners optical storage devices may pose a challenge during installation. However there are an abundant number of well credetialed members here on the Forum that are eager to help.

Regards,
Adrian

mcleod55 said:

LOL I've been downloading them already. The only thing I can't figure out is the chipset driver they have listed is NVIDIA instead of AMD

I believe that you may have a ATI grfx card aboard.
If so check the AMD website for the latest ATI Catalyst driver set that was released in September.

Teerex said:

ratePV said:

Also it does hardware DEP reducing system load.

I think 32 bit does hardware DEP too. Mine does..

True...it does that since Vista x32...ooops

Follow the attached link for your MOBO SPECS:
ASUSTeK Computer Inc.

You have an ATI video card aboard, not NIVDIA.
Use the latest ATI catalyst driver if you are going to set up Windows 7 in 64 bit. Any problems or challenges don't hesitate to ask.

Regards,
Adrian