For wallpapers, open the image file in Microsoft Paint, go to File -> Set as Background. There are 2 options there.. Although I never did it this way except once, I think centered will work the best. If the access to the Display dialog was denied, then a message should come up saying that.. That's how it is in my school. Maybe it is a virus or spyware that does that, or windows just screwed up. For free online antivirus scan, try the Trend Micro website . Ad-aware is the best for spyware - both effective and user friendly. If you want a free antivirus program for your computer, you could download AVG free antivirus. I don't know if repair on windows would work, but I don't think it is a Video driver too.. Do other options in Control Panel still work (i.e.: System)?