Everything I am hearing from Anandtech, Tom's Hardware, etc., etc. says to avoid installing the 64-bit version of Vista- for now at least. Reason? Lack of mature 64-bit drivers for all those peripherals in your machine. Besides, they all agree that other than impressing someone by saying you are running Vista 64, there is little or nothing to be gained (again, for now) by doing it.
So do yourself a BIG favor and stick to Vista 32 until the market matures enough to warrant moving to a 64-bit world (and that will be a ways off...).
pw
