update: I did the following:

- merged all the data drives (ie: not the boot and install files partitions) into one big 107 gig partition.
- downloaded/moved files over
- tested burning capability -- failed
- went out and bought new dvds
- burned
- it works

Why? I want to know why I have a stack of 40/50 dvds which seem to all fail. I would understand if it were one or five or even ten, but it seems as if all the dvds aren't working. Bizarre?