A couple of different things we can try here...
Firstly... Try uninstalling your Java from the add/remove programs and then re-install the JRE 5.11 offline version....(4th one down)
Java SE Downloads - Previous Release - JDK 5
No luck...Try deleting your preference folder...
Fixes for Limewire when LW isn't operating as it should
Still no luck...Could you have a look at the modem/router (the one that connects you to the internet) turn it upside down and see what it's name is and the model number...
Also with your test page not working can mean that your ISP is shaping your connection now...CableVision/Metrocast are known to do that...