We're going to use Mencoder and Mplayer to backup a DVD you own into a DivX file.
A DVD can have several "titles" (parts), and the actual movie is not always the first one. Replace "2" in the command above with any number, beginning from 1, until you find the part you want. Keep that number in mind.
The language you want is not necessarily the default one either. Run this command:
Replace "2" with the number you found earlier, and "en" (English) with a two-letter code for the language you want (fr for French, etc.).
The DVD will probably have black borders at the top and bottom of the movie, and we don't want them in our DivX (they would make the file pointlessly larger), so we need to crop them out. Run this command:
This will make Mplayer start playing the movie 60 seconds after the beginning (replace "2" with the right title number). Navigate in the movie (Right and Left arrows) until you reach a sequence that is bright enough to let you clearly see the movie's borders. Close the movie and look at what Mplayer has been outputting in the terminal: lots of lines like this one:
The part between brackets is exactly what you'll need to use in a few moments to get the right crop.
We're all set, let's encode the movie. We're going to do it in two passes (better quality).
Of course, replace "en", "2" and the crop options with what you need. The "bitrate" value is usually set to how much disk space (in Kb) the video will use for each second. However, by using a negative value (here -700000) you can just ask for a (very) approximate file size (here about 700 M) and Mencoder will calculate the bitrate for you.