You need an application to convert it from DVD video to a different video format. Most of the ones I have seen are not free, so maybe someone else can chime in.
I use Cinematize(<<Link) at work and have had amazing results. There is little to no quality loss in the transfer. I convert to Quicktime (.mov) and then edit and (re)compress in Final Cut. It's $60 for the basic version and $130 for the pro version. BTW, this is NOT for ripping copy protected DVD's.