Can I re-install windows xp on a computer that had windows xp but now has crashed? And which one does it need to be... windows xp home edition, with service pack, or can it be windows xp upgrade..., or what exactly.., and do I have to have a license to do so?You can reinstall Windows XP (but I think a Repair Install will suffice).
All you have to do is Boot from the CD. I don't recommend you reformat (completely reinstall XP) your computer if you WANT to keep your files because it will remove them all.

If you want, we might be able to diagnose your problem.I'm glad you told me that, because for this computer I have alot of music that I would like not to lose if at all possible. -- I think it just got a bad virus or something because one day it just started getting slow and I think it may've even started to freeze, and I decided to turn it off then turn it back on and it was "Gone"!....  Now when I turn it on there's only a small line at the top left corner that's flashing.- Did the spotmau on this one too and it said windows wasn't even on there.What's Spotmau?Spotmau is a disc I bought that is suppose to reboot any computer. I've read alot of good reviews on it and someone from this SITE also recommended it. I  like it so far I just can't go any further with it until I get the windows ready to  install. Hopefully this will be within the next TWO DAYS.  Waiting on Ubuntu to come in the mail...