I'm having the same problem as everyone else. About 1 to 1-1/2 hour of play it freezes. I have a Sony DRU-700A. The discs I'm using is Memorex DVD+R Recordable. I sure would like someone to come along with the solution.
Try lowering the burn speed, if that dont help change the media (memorex don't seem to get very good reviews here at aD)
Lowering the target file size down to 4,300MB helps too by keeping the burn from the very edge of the media where most errors occur