RipIt4Me will rip the DVDs to your harddrive so that you can run them thru DVDShrink. It's free and works wonders.
Another great free ripper is DVDFabDecrypter. Virtually does similar thing as RipIt4Me, so you can run the rip thru DVDshrink.
If you prefer the convenience and speed of on-the-fly decrypting straight thru DVDShrink from the DVD itself, then I would recommend that you try the free 21 day trial of AnyDVD. If you like it, you can purchase it after the free trial period is over.