Version 7.0 (you just missed out) was the first to offer the ability to burn to DVD media (although I believe it was limited to DVD-R), and the current 9.0 can backup to any DVD+/-R/RW media, as well as CDs, Zip disks, various hard drives, and networks. (You can click here for the datasheet.)
Hope this helps,
I have version 6.0 and although it created the image for my XP system ok, I'm wondering if the newer version(s) have the ability to burn to a DVD type disk instead of CDR-W only? It took 6 disks whereas perhaps it could have done it in two instead.