Cave, I built an nForce system in December. I'd suggest putting Win 2000 or XP on it. (ME will work if you have NOTHING else.)
The guy I built it for hasn't had any problems with it that I know of.
I really liked the board itself. Look for my thread on about December 20 called "I'm about to build an nForce system."
I posted a lot of info there.
My only complaint is that the manual is pretty bad about showing jumper and connector locations for things like the power switch etc. (The USB header looks almost like the connector the power switch, HDD led, etc hook to.)