When Limewire 3.4.4 is connected, my system crashes - MAC OS 10.1.5

First it says that the connection is broken then I can't open nor close Limewire or any other application and in the end when I try to shut down my computer, it doesn't work, I have to press O/I button.

It's the same problem when I'm trying to upload files with Fetch for example.

Do you have any information about that?

Many thanks (I'm desperate)!

Julien