What happend to the system and my downloads?
 

I use an imac that we just got in sept. I downloaded limewire and it was working just fine, and then one day I went to listen to an already downloaded and I thought imported song on itunes, and it wouldn't let me giving me some strange message. I then went to try and start up the program and it wouldn't let me, with another strange message something about Java???? I'm so confused as to what happened, it worked just fine!