resolution problem that is really doing my head in!!!

i'l start at the begining when this problem randomly seemed to pop up.

I felt like playing GTA 4 again so i reinstalled it on steam. for some reason i'd get an error saying i need xp service pack 3 to play. (i have vista and i was able to play gta4 no problem months before) I went on the net to try and find a problem. a few ppl said update your drivers and such.

i went to the nvida site and searched for a new driver. some some reason it was recommending me a 190.38 driver or something like that even though I had a 196. something driver. i decided to install the 190 driver anyway.

ever since then i've had problems. every time i restart my PC the res will be 800*600. when ever i open progams such as steam my monitor will go black for a few seconds. oh and GTA 4 still dusnt work...

ps. when i go on the nvidia site and let it scan my hardware to find a driver for me it recommends some random linux driver?! wtf.

any 1 knw whats going on?

i just used system resotre and restored my PC to a few weeks before. drivers work fine now. unfortunately doing this has totally messed up my norton 360... auto protect wont turn on and neither will email scanning lol.