XP Media Center Edition (MCE) is a version of XP with multimedia interafce handling in its core. It's a rewrite of the rules that the OS follows to talk to multimedia interfaces such as sound cards and whatnot.
This means that many interfaces for video and audio, and USB devices that were supported under XP Pro or Home won't be under MCE. At this point, the device vendor's word is what I would take as final on the subject.
Maybe there is the barest wiggle room in this fact, however: XP MCE comes as a 2-cd installation and I have read reports that intsalling MCE by using only CD1 and not CD2 leaves a "vanilla" install of XP Home. In other words the MCE changes to the OS are localized on the second install disk and you can supposedly halt your install at the point it asks for CD2 and this will leave behind a working vanilla XP home install.
I have not tried this myself, so don't quote me.
Another caveat: of course these days you're lucky to even receive facory install disks at all when you buy a preinstalled PC of any kind.
-r