How do i play back-up DVD's.

I understand from your post that you've ripped a DVD to CD (not copied a DVD to DVD-R).

I also assume that you boot backups using the Utility Disk as the Boot Disk. This constrains your rips to be 624MB TOC (as in Properties in Windows Explorer). If they are larger, like closer to 700MB, you can't play the rips unless you load an image of DVD Region X behind the Utility Disk and then the rip behind that.