Open Question: Windows Media Player and iTunes MP3 Problem?

Ive tried multiple times to change my default media player from Windows Media Player back to iTunes but whenever i try and play an MP3 from outside of itunes, Windows Media Player is opened up. It seems i can't uninstall windows media player. MP3 files in my itunes library play fine from itunes but when accessed from their folder open up Windows Media Player. All MP3s have Windows media player's icon instead of iTune's icon and MP3s cannot be imported into iTunes. How can I fix this?