Thanks for the info
While Prodisc F02 can be good with some burners, other burners may not burn them so well, especially if the person that sold you the discs burned them at the maximum 16x (highly likely).
There’s a very good chance, it’s the media. Added to that, NECs aren’t the greatest readers if a disc is badly burned.
I’ll ask this anyway, but your drive (and your son’s) reads other burned DVD media OK?
Edit: Try ISOBuster, or ISO Puzzle, with the help of those programs, you may be able to recover all the files, if you don’t want to send the discs back yet again.