Need help with my laptop

Ok…here is the problem…Recently I had a friend install a fresh copy of Windows XP (bootlegged). At that time I couldnt find the original Windows XP discs so I had to go that avenue…The other day I found the original discs that came with the laptop…So since I found them, I wanted to install a new copy with the “real” key. Well the problem I am having is that when i start the installation, it will stop with a window saying" Verison your trying to replace is newer than the one your trying to install" or something like that…Can anyone help me where they can bypass that so I can install a new copy of Windows?

If anyone can help me, please PM me…Any help would be great

completely unistall windows. kbye

fdisk that baby and then insert your “real” xp disks