I have installed and uninstalled various codecs, on various words of advice. I currently have a neat little application called: "AVI to VCD/SVCD/DVD Converter v2.48" I have also followed the conversion guide on this site: http://www.afterdawn.com/guides/archive/convert_avi_to_dvd.cfm For both of these, I have noticed similar end results when it comes to codecs installed. One codec allowed me to begin rendering but it removed the letterbox, squashing the picture into a square. The most recent codec I have installed is DivX521XP2K (from divx.com). It not only removes the letterbox and squasges the picture into a square, it also drops a watermark into the corner. Removing this codec fixes that issue, but... I cannot find a codec that will keep letterboxes as they are or add a little, to allow me to keep correct aspect ratio. Where can I find one?