DVDXCopy is what I used to use. The company has folded so it no longer has any kind of support. Even if you had a copy you would be unable to backup many of your newer DVD's (I haven't explored the possibility of using a different ripper with it).

DVD Shrink is very good. It can be found here.

www.dvdshrink.org

Try that one and see how you like it. Best of all, it is Freeware.

Shag