Some parts will work on XP...others not so much. The logoff and shutdown screens, and control panel will definitely not be skinned, so will look like the old XP (Luna).
My XP machine died last year, so all I have to skin with is Windows 7. You could try applying the skin and see what it looks like. It shouldn't hurt your computer to check.
My XP machine died last year, so all I have to skin with is Windows 7. You could try applying the skin and see what it looks like. It shouldn't hurt your computer to check.