I bought Windows Vista Home Premium and installed it.
But there is a problem I have a Nvidia GeForce 4 MX graphic card
(I know Its WAAAY old) and now for some reason I cannot set resoulution
higher than 800x600 dpi.I have DirectX 9c but I cant find a driver for my card
for Vista!Please help quickly!

I doubt the Card can run any higher on vista because their aren't any ok drivers for it.If possible get another card and it might run higher.

Hi Stefcky, and welcome to PCHF!
Your GeForce 4 MX is a little bit old to handle the graphics for vista, as AMDPhenomX4 has mentioned. If you really want to experience the full graphical performance of Windows Vista, it would be better to upgrade your video card.

I actually have this running on old GeForce MX without problems. (no aero of course) but i can run it fine to 1280x1024