VOB (DVD) / OGV (Ogg Vorbis video) to MPEG / MJPEG

To encode to MPEG-2:

mencoder -idx infile.ogv -ovc lavc -oac lavc -lavcopts vcodec=mpeg2video -of mpeg -o outfile.mpg

To encode to a Windows compatible MPEG-1:

ffmpeg -i test.ogv -b 2500k test.mpg

The -b option specifies the video bitrate.

To encode to an MJPEG, suitable for editing, use:

mencoder -idx infile.ogv -ovc lavc -oac pcm -lavcopts vcodec=mjpeg -o outfile.avi

Alternative: install libav-tools and run:

avconv -i infile.ogv -vcodec mjpeg -acodec pcm_s16le -qscale 2 outfile.avi