First of all, is this a IDE drive, or a SCSI? My assumsion is that this is an IDE drive; there is no section on SCSI in your Device Manager.
If this is a IDE drive, then this is what I would do:
uninstall either the secondary or the primary channel where your DVD drive is on, then reboot your computer. XP should redect whatever was uninstalled, and another reboot should bring your DVD drive back online.
If this does not work, try unstalling the busmaster driver and reboot the computer.