I currently use Vista 32bit with 4Gb's Ram, and a Nvidia Geforce GTX 285. I was thinking about upgrading my system to windows 7 64 bit and increasing the Ram by about 2Gb. Q do you think its necessary to do this upgrade now as i use my PC for Gaming.
with 32bit, your maximum memory is going to at most be 3.5GB. I'd move away from vista just because its awful. 4gb win7 should be ok so save some money.
I would go for the upgrade, but don't necessarily expect to see instant rewards in every game, think of it as an investment for the future.
The extra RAM will not result in a noticeable improvement for games. It will be excellent if you were working with large spreadsheets and databases though.
If Win Vista works fine for you, then I wouldn't bother upgrading.