Samantha, I have been using DVDShrink 3.0 b5 to backup dvds without losing any extras or audio tracks, and the quality is not jepordized. If you would like more info
here is a good guide on using it. If you have any questions, feel free to email me.
The results I get using DVDShrink are excellent, I can't even tell the difference to the real dvd, and I have a very extensive hometheater.
Steve