my hard drive has 4 partitions and running ME on C: drive. I want to Install a full XP pro ver. in place of ME without loosing any data on the 3 remaining partitions. Can I change the boot sequence to cd-rom, pop the XP cd in and let it format my C: drive and then do a clean install of XP? Or is it necessary to delete that partition and then recreate it? Since I am not using the upgrade ver. of XP, I wasn't sure how the process should work.

Full versions allow you to upgrade unless its an OEM copy. The OEM copies are meant for new / clean hd's. Why the heck MS goes thru goofy little games like this i will never understand. I havent tried an OEM copy of XP yet but all the previous MS OS's have been this way. And with the previous versions a workaround exists to use the OEM copy as an upgrade. Formatting [clean install] is the best thing to do. The other partitions arent affected and the only potential data loss will be favorites/emails anything on C:\.

Don't format c: if you have other operating systems other windows me. If you do, then you can't boot. It sounds like you do have other OS's (my hard drive has 4 partitions and running ME on C:)

I am running only ME on my C: drive and have no other Operating Systems loaded on the remaining 3 partitions.