Mplayer does not seem to detect the aspect ratio of connected monitors. You have to specify the monitoraspect parameter. If you have one of those 16:10 laptop widescreen monitors this might greatly increase your viewing experience (put monitoraspect=16:10 in your .mplayer/config file). The Xine player autodetects this just fine btw.
LoLoCoJr
Andy Lo-A-Foe's weblog
