I've done exactly what you wish to do with
AoA DVD Ripper. You can use the demo version of this software to rip short clips from any DVD. If you decide you want to rip an entire DVD, you'll need to purchase the software.
It worked so well, and since I found I could also use the software to rip DVDs to play on my Pocket PC, I wound up buying the software.
Let me know if you need any help.