Hi nivin,
I've never reinstalled my Windows but this might be helpful:
http://www.pcmag.com/article2/0,1759,1202609,00.asp

More reinstall info:
http://support.microsoft.com/default...&Product=winxp

Also some info about backing up:
http://www.microsoft.com/windowsxp/u..._03july14.mspx

and some backup basics:
http://www.microsoft.com/athome/secu...te/backup.mspx