I just picked up Season I. I know some time ago there were issues with the discs, I did some searching and the only thing I could find that was consisten was Disc 1 locking up on Episode IV. So I have a couple of questions: 1. What are the tell tale signs to know if I have a defecrive Season I set? 2. Was this issue ever fixed? 3. Is there a specific thread that talks about this issue in depth? Thanks.