If you upgraded from an earlier OS and saved that info, you can go to
Control Panel, Add/Remove Programs and remove WinXP. If you don't see that
option there, you will have to reformat the HDD and then install WinXP Home.
If you can remove WinXP Pro, then simply put the WinXP Home Retail upgrade
CD (do NOT use an OEM version, it won't allow an upgrade of the OS) in your
drive and follow the directions for installing an upgrade.
If you can not remove WinXP Pro, then you should save your data to removable
media (spare HDD, CD/DVD, Jaz, Zip, etc.) so that you can reinstall it when
you are done. When you reformat your HDD, you will LOSE everything that is
on the HDD.
