If you have an xp oem or purchased disk it will not delete any files-If you have a compaq,dell or gateway restore disk it will reformat your drive and youll lose everything. your settings generally will stay intact
Get a second HD Copy it there and use it for this stuff.
Then do a complete install if you really think you have to.
Thats what i did,5000 + mp3's on my D drive.
Yeah, it'll only change C:/Windows and C:/Documents and Settings because those are the only Windows based Folders. Programs will all be uninstalled of course but its easy enough to reinstall them. With an OEM the files will all stay safe if they're not in the above Folders.
just dont format ur drive install the xp pro in top of the partition so when its done just go into search and type in the name of ur song and it will find it, it works for mine.