no sounds except for windows media player files

HELP SOMEONE!!
i bought a dell desktop a few years ago and all of a sudden the speakers stopped working[speakers that i bought with the computer]. My cousin suggested that i download a audio-driver off of dell.com. thats what i did and well i played a song, windows media player came up and well it worked. but then when i was on the internet i noticed that they weren't working. So does anyone have a good idea of what i culd do to get the sound working all around?? im don't know alot about it either so culd you keep it simple?

Go into control panel, go into sounds and make sure its using your soundcard as the sound driver......if this dosent work install drivers from the sound card company...