System restore is purely a GUI based tool for light recoveries. If you’ve seriously damaged your system, then I’m afraid most of the time with Windows a reinstall/repair install is the only option. But as megamaced pointed out, describe the exact problem and we’ll try to help.
Although this is a two year old post a Guest is looking at it right now.
Let me just explain that XP does not run on a DOS platform and all Microsoft Operating systems have not done so since ME.