It's not the Region you need to fix its the format that the video is in ! Can I ask are you in the US and is it possible that you have a European PAL DVD that you are trying to play ?
There is a program that can do this but it's very long winded (I did it once years ago) and time consuming, it's often easier to just purchase the DVD for the country you live in. I think I used TMPGEnc but it was a while ago and I did also have TMPGEnc DVD Author as well....