How Do I Make Windows Media Player My Default Player?

Right click on any music or video file which the windows media player can play, on the options you'll see "open with'. Take your mouse over there & you'll see a group of programs which your PC has, & at the bottom of the list there should be "more" or something like that written, click it.A new window will pop up, there you can select which program you want to play the file with, do that, & around the lower part of the portion there should be an option to make the selected program the default one. I use windows XP & that's how i do it, it's probably the same with windows 98, but i can't say about Windows vista since i haven't used it yet !