1. I guess I got to tell the company that they sell bad discs.
2. Maybe, maybe not. Some discs work, others do not.
3. Perhaps, it is in any case, old and tired. Which incidentally was why I ordered a new computer for a few months ago.
I believe that my discs, although they would not be of the highest quality, is too good to my current burner. Lightning UK! said that the discs have a different dye than my earlier discs. Hopefully, this problem will solve itself when I get the new computer. If it fails too, then I can consider acquiring new discs. But to run away to the shop is not the first thing I do. It was that I tried to say a few posts ago.
I hope we understand each other better now!
EDIT: I have received my new computer and tested it with the disc. It worked. Like you said, it's probably my old computer which can't use the newer discs.
Again, I'm sorry if I offended anyone before, it was not my intention to do.