I've had Handbrake recommended to me, but, while it's worked well for others, I've always had trouble with it.

Instead, I use AutoGK . It can't extract the files off the DVD, but often you can just "explore" the disk and copy the files yourself. (The biggest ones from the video_ts folder.) If not, DVD Decrypter will do the job.

When in doubt, think about penguins. It probably won't help, but at least it'll be fun.