Useful tip for backing up to CD in XP courtesy of WinntMag.
Back up to a CD-ROM—A major limitation of XP’s Ntbackup utility is its inability to select a CD-RW drive as a backup destination. To work around this hurdle, open Ntbackup, select the files to back up, then select C:\documents and settings\username\local settings\application data\microsoft\cd burning\backup.bkf as the backup destination. When the backup finishes, XP will prompt you to write the files to the CD-ROM