Please help with wmp

i never ever thought i would have to uninstall this great player, but i downloaded WMP 11 beta. its hard to use. i had a problem w/ nero and their support team told me to reinstall it. so i did and it tells me i need to end WMP. so i do control alt delete and end> procees> wmplayer.exe the little crap pops up again and i cant end the process. so i was like screw this, and i went to uninstall it, the crap didnt come w/ an installer and i cant do it from add/remove programs. i cant delete program files because there in use! what do i do. i hate microsoft 4 this.