Replying to My computer is screwed up. please help.

ok my screen resolutioin is like 400x500 and i have a 1032x1628 resolution screen or somethin. so every around this little square is black. and then all of the normal colors have been inverted so everything looks like its negitive. like black is white and vice versa. i know how to normally fix it but every time i go to proporties and go to settings an error messege pops up and says i need to shut down. then it says my ati driver is installed or its not working.

so i need to know how to fix it other wise i will be sad.

your help is much appreciated.