NEVER UPGRADE AN OS!!!
Backup the files you want to save from your system now, then make a boot disk and in the system root folder, copy the file format.com to the boot disk. Next, restart the system with the boot floppy in and when you get to the dos section, you should be at an A:\>. If not, type "a:" and hit enter. Next type "format c:".
When it finishes formatting the hard drive, put the Win XP disk in and go through the installation.
To install a new OS as an upgrade almost always has problems, and will eventually crash and force you to install fresh anyway.
Buen suerte,
Smar969905
Young, foolish, and occasionally knowledgeable...