Hack Attack: Burn almost any video file to a playable DVD - Lifehacker: "DVD Flick is a free, open source DVD authoring tool that will take care of pretty much all of the legwork involved in authoring your DVDs. So thank the gods of open source and go download it here.
In order to make a DVD that you can play on your DVD player, your video files need to be encoded in MPEG-2 format. What makes DVD Flick special (aside from the fact that it's free) is that it handles all of the necessary transcoding of your AVI, MPG, MOV, and WMV files (among others) to MPEG-2, and then authors and burns your DVD all in one fell swoop - meaning it's very simple for anyone to use."
