HandBrake is a useful open source tool that converts DVDs to MPEG for free.
Features of Handbrake
Forget paying for a program to rip your DVDs to your computer ever again. Considering HandBrake doesn't cost a dime, the application delivers exceptional results.
Handbrake lets you perform two-pass conversions and codify a double soundtrack. Another great feature is the bitrate calculator, which alters the quality of the video according to the final file size you wish to achieve.
You can even trim the black bands around a movie to maximize the size of the file. Other features worth mentioning are chapter selection, basic subtitle support (burned into the picture) and grayscale encoding.
Simple to use
Converting any type of DVD through a simple-to-understand GUI, the program whizzes through the process of producing an MPEG-4 file to save on your machine.
Note that you'll need to have the right codecs installed for the type of file you wish to convert such as DivX, Xvid, OGM, 3ivx, etc. Handbrake supports any DVD-like source such as VIDEO_TS folders, .VOB, .TS files, DVD images and real DVD. However, unencrypted-protection methods including CSS are not supported internally and must be handled externally with third-party software and libraries.
Although I experienced a couple of crashes with this version of HandBrake, it's nevertheless a great open source solution for ripping your DVDs.
A robust encoder
HandBrake is an incredibly impressive and efficient video encoder for all of your MPEG-4 ripping needs. Best of all, it's free!
HandBrake supports the following formats
File format: MP4(M4V) and MKV
Video: H.264(x264), MPEG-4(ffmpeg), MPEG-2(ffmpeg), or Theora(libtheora)
Audio: AAC, CoreAudio AAC/HE-AAC (OS X Only), MP3, Flac, or Vorbis. AC-3, DTS, DTS-HD, AAC and MP3 pass-thru