Zodiaq~, sounds like it is ur video card that's causing the problem. If u have any other monitors around, try plugging that in to your computer. If its no better, try installing a new driver for your video card.
It's probably something about your hard drive. It just might be the color setting you have for your comp as well.
go open the display properties, click on the Settings tab, and on the color menu, set the color to the highest (most of the time, True Color 32 bit) if its something like 16 color, or 256 color, try changing it. because if i change my computer's color to 16 color, nearly the same thing happens (except that I have Win2k now)
Question: What video card do you have? (mebe that might give us more infos so we can help)
Hopefully my suggestions helped

Wasupboy