How timely is this? Elliott Back has written a quick tutorial on How to rip a DVD.
Ripping a DVD to xvid or divx avi is really quite easy, if you have the right tools.
YouÃ¢â‚¬â„¢ll first need to download DVD decrypter and auto gordian knot (autogk). DVD decrypter allows you to rip the raw DVD video and audio data off of your disk drive, decrypt the CSS protection, and finally remove any other protection schemes, such as Macrovision. AutoGK is a package of codecs and a GUI interface that will take the raw DVD data through an AV processing pipeline to produce a single windows video file.
and the rest is in the article.