If you are mac user,I recommend you to use
DVD Ripper for mac .
Since it
rip DVD to all sorts of video files (including MP4, WMV, AVI, MOV, M4V, 3GP, MPG, MPEG, FLV and so on )and extract DVD audio to various audio files.
powerful edit founcation . select the chapter/subtitle and audio track you want, trim any video, preview your movies in real-time,cut off the black edge of the movie and merge more than one DVD chapters into one file on Mac OS X.
copy all of your DVD movies to computer by 1:1 perfect Video & Audio quality.