movies are not recognized as even being there

[SolarWar]

when i insert some movies they are not erecognized by my computer and it is a 3 month old HP pc i dont have the actual specs in front of me, but they dont even open up in my DVD player let alone allow me to try n copy them.. any particual reason for this or anyone have a similar problem?
some movies in question
Man of the House
Taxi Driver Collectors Edition

[redwudz]

This may not be related to your problem, but Man of the House is listed as having ArcCos encryption protection, not sure about Taxi Driver.

I don't know if that might prevent it from being played or recognized in a computer but it does effect trying to back it up.

Guess I should mention DVDFab Decrypter should allow you to rip it to the computer hard drive, if you can get the computer to see it.