Hi, I've just reformated my computer, a MDG windows XP version and I am not able to change the screen resolution from 640 by 480 pixels, I do not know what I need to fix this problems, any suggestions... I really need to fix this problem.

Did you try --right click on your desktop/properties /settings/ change screen resolution?

Yes... Here's the thing, I reformated the computer... I have an MDG computer, when I go to properties/settings the screen resolution is stuck on 640 by 48- pixels and when I try to move the arrow it wouldn't move, and the colour quality is set on Medium (16 bit) and the drop down box has no more options in it... I think it's missing a driver or something... I'm not sure.

What's happening is you didn't load the drivers for your particular video adapter so its reverting to SVGA as the default. You need to find out what adapter you have and load the drivers for it.