I've mentioned this before, when I was talking about 'user.menu' for fluxbox, back in Part 4 - usermenu but having just configured it to use the root menu I'll explain further. It describes itself as 'A media player written in python, GTK and utilising gstreamer. Similar to totem but without GNOME dependencies.' The latest version is 0.2.14 dated 26/02/2011.
You can get it from its http://home.gna.org/whaawmp/downloads.html and then to install it for any user to use -
sudo python setup.py install --prefix=/usr
which puts it into /usr/local/bin.
I've tested it out with .avi's, .mp4's, and .mpg's and its played them all successfully. It can be paused during playing by pressing the [SPACE-BAR], it disables the x-screensaver, and shows how much time is left playing. It can play dvd's, although I've never tried it like that, and is an all-round good egg! So here's the obligatory screen-shot -