Try uninstalling your Java from the add/remove programs and then re-install the JRE 5.11 offline version....
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11
If that does not help with your problem try deleting your preference folder...
Fixes for Limewire when LW isn't operating as it should
Your router has a firewall...You can Port forward to allow Limewire through...
These are your instructions...
Port Forwarding for the Belkin F5D7230-4
Your modem also has one as well, these are the instructions for that...
Port Forwarding for the Efficient(Siemens) Speedstream 5200
(just remember you only need to set up a satic IP for your computer just the once, after that you just need to log into your modem/router and set the port numbers...)