Notice I did not say g
mplayer but rather just mplayer
This will attempt to load up mplayer onto the screen w/o the gui.
Try that to see if it works
If it still doesnt work ... what does it say failed?
If its video do mplayer -vo help to choose the appropriate driver
if its audio problems -ao help
Once you get it working w/o the skin then try
gmplayer -skin <skinname>
for instance I have a folder called Orange in /usr/local/share/mplayer/Skin/
so I would do
gmplayer <possible video/audio options from before> -skin Orange
You could also create a symlink to the skin u want to use and call it default
ln -s Orange default
then you no longer need to specify the skin, it will simply think of it as the default.
Also try running it as a normal user rather than root.
Hope that helps