hmm....
i think there is a way to uninstall xp and "return" you system to a ME installation, but if you have ME and XP discs you should be able to do it manually.
Just try booting from your ME discs. I haven't installed ME from discs before, but I assume there is a "start from scratch" option that will remove xp from your disk.
If that doesn't happen/work, here's how to wipe out xp manually. I'm not responsible if it messes things up
First, if you are using the NTFS filesystem (if XP was preinstalled this is probably what you have) the following procedure may not work.
1) Get a DOS boot floppy. Probably the fastest way would be to make a "startup disk" on a win98 or ME computer.
2) Boot from the disk and run FORMAT C:
You will lose all data on you windows "C" drive
--OR--
Boot from the disk, run FDISK, and repartition the disk
Note that you will lose all data on your partition(s) Also please note that if you bought a pre-built system from a manufacturer, you may have a "special" setup that can make either of these steps cause undesired results. You have been warned
3) Now boot from you ME CDs and it should install.
hope this helps...
~psi42