I recently lost my desktop w/XP and replaced it w/a new system running Vista. I was so disapointed with Vista I bought a used tower whose OS had been removed. On it I loaded a OEM copy of XP from my original computer which loaded find. The hardrive was 20G. I could not, however actvate XP and it expired in 30 days. I then bought a new XP Pro and did not know how to remove the old XP so I loaded it over the original (I think). It works fine but I now have only 10G on the HD. Suspecting I have 2 OS and a partitioning problem I now thought I should remove the latest and start all over again. Loading the XP Pro CD does not appear to give me an option to remove the OS. Can anyone give me a little help? Thxs!