Steph;
NTBACKUP is a very basic back-up application and not capable of
backing up to CD: http://support.microsoft.com/?kbid=315255
You can back-up to another location on the hard drive and then copy
that to CD.
Or you can get a 3rd party application.
First get some decent burning software like Easy CD Creator, Nero or NTI.
Then get some imaging software such as Ghost 2003 (works very well with XP),
Acronis or any good imaging program. Drive Image 2002 is not guaranteed to
restore XP although it will image on XP.
Good Luck