You can't just copy a dvd. There are protections. You can only fit about 4.38 gb on one dvd. You have a few options. There is
dvdxcopy, that is what I use. It usualy requires 2 discs for a movie becuase most movies are bigger than what 1 dvd holds. This program keeps all extras and true dvd quality. And there is
dvd2one or
dvd shrink. These programs compress the movie to fit onto one disc. The quality loss isn't very noticable if at all.