Can't Burn DVD

Hey,

I have ripped a DVD that I own and when trying to burn that via Toast 8 Titanium or Popcorn 2, I keep getting these messages... any ideas folks?

Please Help!

David

EDIT: This is being done on an 17" iMac C2D 2.00Ghz with superdrive info listed below. It has 1GB RAM, 160GBHDD and ATI1600. It should also be noted that I have done this process literally 100's of times in the past with no problems.

Machine Info & Error Messages:

 

Ah! I haven't even attempted using another ripped file to see if that works, so I'll try that first. Thanks for your suggestion.