I need to reinstall xp, but I don't have the original xp recovery disc, what do i do?

I need to reinstall XP Professional on my desktop, but I do not have the recovery disc for it, however I do have a completely different XP Professional disc that is activated on a friends laptop. Is there any way I can either create a new recovery disc with my desktops xp, or somehow use my friends cd to reinstall it. Note: my desktop is also running SP3 and my friends disc is a SP1.