I have a handful on discs that play bad poorly on my iBook but play back okay on my standalone DVD players. Amusingly, the most reliable DVD player in my household is the oldest: a standalone Sony from circa 1997.
As for your Rest In Peace title, you might ask the company you purchased it from for an exchange, but since it's not an original, all bets are off concerning playback compatibility.
If you scratched the Strokin' to the Oldies disc, well, that's your fault and you will have to pony up the cash to buy a new one. There are scratch removal kits/services/techniques, but nobody can guarantee that any of these will restore the disc's functionality. You could also damage the disc so it doesn't play anywhere.
Good luck.


