Lots on noncommercial ones too...
Take your pick of rippers... DVD Decrypter is probably best known, but there are several other - Smartripper & ClaDVD.
http://avidemux.berlios.de/ - I've been tinkering with this lately, not the most intuitive solution, but has some good features.
Encoding to MPEG2 walks straight into the middle of the Patent/licencing issue, same as MP3.
The best commercial encoders, are probably a bit more certain in the speed/quality issues.