Please help me, I don't know too much about computers. I'm having trouble wih my Limewire can someone please ?

The problem is, I've must have installed a media player that is not windows media player. Now my limewire songs apear with an icon next to the song. It use to be the music note icon, because of this I can't no longer download the song chosen or drag it to I tunes. Someone left me a message and told me that I need to get back windows media player. Explain to me how I do that, where in the PC do I go to change this. Please tell me step by step how to do it.. HELP..