Dvd Copy Failure

[PWrig]

After using MacThe Ripper or DVD backup I try to burn using Toast 6 - whilst finishing sessiion message box indicates an illegal request. I have to force quit Toast. DVD will play on the external LaCie dual layer drive which burnt disk. DVD will not play on G5's internal drive or other DVD players. I am doing full extraction, no compression (burning to dual layer disk with dual layer burner) have set to region 4 (which is my region and that of the DVD's being backed up) have also tried enabling all regions. What can I do to play DVD's on other players than that of LaCie?

Using G5 with OS 10.3.9. Internal super drive single layer burner only thus using external burner