I would agree with phishhead.Go for a reformat rather than an upgrade.
The problem with just upgrading from ME is you will have a lot of redundant ME files and drivers left on your system which will cause conflicts with the XP ones.
I would suggest you FDISK the 10gig drive and set it to primary slave then set the 80gig to primary master.
Go into your bios setup and in "advance bios features" change the first boot device to CDROM.
Save and exit the changes then reboot and pop your xp cd in.The installation setup should then autorun.
When it asks you what partition to install on select your 80 gig drive and format with the NTFS file system (not quick format).

With regards to drivers,looking at your system specs in your earlier post,XP will have all the relevant drivers for your hardware.

Hope that helps.