You haven't given us much information to work with here RegKing. Are you talking about a commercially made dvd movie? If so, you will need to break encryption on the movie. For that I recommend DVDFab or AnyDVD. Both are commercial programs, but have free trials to test their capabilities.
DVDFab is an all in one program, in that it can decrypt and rip the movie to the hard drive, and shrink it to fit a blank dvd. You see, most commercial dvd movies are too large to fit onto a blank single layer dvd without taking extras out, or compressing the video.
AnyDVD just does the decryption, but you can combine it with a free program called DVDShrink and accomplish the same things as with DVDFab.
DVDFab does have a free section within it, called DVDFab HD Decrypter, which will decrypt and rip the movie even after the trial ends, but it won't compress. And it is no longer updated at the same pace as the paid version, so you might run into some movies that it won't work with in the future...at least until they decide to update the free section.
If you are asking about a dvd that isn't encrypted, then it is easy to make a copy with ImgBurn (a free burning program). Just make an ISO file of the original dvd, then burn to a new disk.