Can Someone Answer a Disney DVD question ?

[disneyrex]

I ask because i bought the Tangled Blu-ray + DvD combo pack i've watched the blu-ray a couple times since i got it and yesterday i was going to check out the regular DVD on my laptop (bringing it on a trip in a few days) and it doesn't play it tries to load for a little while then nothing happens and i know there isn't anything wrong with my drive. My drive is 2 years old . Now i've tried this DVD on my nephews brand new computer and it played on his. I'm running Vista & he's running Windows 7. Media Player 11 & 12 are the differences there. I've also tried VLC & AnyDVD neither helped. I have a friend who bought the same combo pack i did and their regular DVD won't play on my Computer either. My computer plays all other DVD's i try to watch with no problem. And here's the kicker. I rented a copy of the same type of DVD of "Tangled" from a redbox at walmart today on a whim just to try it and the dang thing plays so i'm scrathing my head here.
What Gives ?