mplayer giving problems
 

i installed mplayer and then i tried playing this file Halo2.wmv but the screen went black and didn't do anything. Then when i moved the mouse, it came back to what i wuz doing. It does that with everything i was trying to play

Try running mplayer from a shell. The command should be gmplayer if you have the gui installed. See if you get any error messages in the shell.

it says bash: gmplayer: command not found
i did run mplayer from shell but didn't give errors

Didn't give any errors when you played the .wmv file? It will produce some output. Can you post the output.