I use my Toshiba laptop to backup some one the DVDs but everytime I play them, it's skipping or freezing. The software I use is DVDxcopy Platinum. Is it because of of the DVD-R is only 4.7 GB while some of the movies is much bigger size and it had to compressed them? But my friend used the same 4.7 GB DVD-R to burn his DVD and it works fine. What seems to be the reason for mine?