codecs

Anyone know where to get codecs? I downloaded Super 13 movie recently, it works, but, i cant hear the sound of the movie. And 'NO' my speakers arent turned off, or, there not plugged in, or, my volume isnt up high enough:\ Im just missing some codecs. I dont really know what a codec is, I...

i really wanna see the new movie, but whenever i play it it tries to dl codecs but it says it fails. i got to windows.com and try to dl every type of windows media 9 codecs but none of them work. some someone help me?