How can I break into a DVD+R that seems to be locked?!?!

I had to reinstall XP. I backed up my files on a DVD+R disk before the install and now I can't get back into the disk. I put in a blank disk and no problem with it just the backuo disk. It's locked or something and I have over 1000 family pictures in there. I'm just hoping there is some way to recover them.
Moderator if this is a hardware issue boot me over there please.
Thanks

 

Could the pictures still be on my other hard drive? I took it out of the old computer and put it in this one. when I transfered the pics I used move instead of copy. Did I really move them or just remove them from the directory? For the present am going to try iso buster on DVD and see what happens.

 

MW.........When you put the disk in, and right click on the drive from "my computer", and click "explore", is it showing any files on the disk?

 

What program did you use to burn the DVD?

 

First I set up the disk with Roxio's Data DVD Project, then I used Windows Backup to do a full backup(3.47G) and a partial backup of files and settings only which was appended to the full back up. In answer to Brian C's question, no it shows no files. I was able to recover 3.93g of the backup file with IsoBuster but not the whole file. I think the appended file has been damaged or is not all there thus Windows Backup won't let me use it. Is there any way to make this recovered file work again? Or how about the other harddrive option?