I am also having the same problem with LimeWire 2.8.x with OS 10.2.x. The 2.7 version I had worked fine, as soon as I went to 2.8 it will begin the launch process but then freeze the entire computer - I have to hit the Reset button to restart.
In another posting, I found this link to the general download directory, seems to have any earlier version you may want.
http://www9.limewire.com:82/download/
I'm downloading 2.7.13 now. Hopefully this will work...will post back and let you know.
Anghara