If you want to forward a port for your router you MUST have a Static IP for it to work. I have a few links starting with this one: http://www.portforward.com/routers.htm

Setting up Static IP: http://linksys.custhelp.com/cgi-bin/...TVUxMA**&p_li=

Port Forw'ding for Linksys: http://linksys.custhelp.com/cgi-bin/...type=search_nl
Of course you should use Port 6346

I don't know whether the Linksys routers use UPnP or not. If it does then port forwarding might not even be necessary. The last step to above forwarding is manual Force IP within LW: Force IP instructions & sample image (& also see 2 posts after that.) If you are using UPnP with your router/modem then setting LW to UPnP should be all you'd need to do.

Configure your XP & other firewalls using instructions here: http://www.limewire.com/english/content/firewalls.shtml

Make sure your Java is up to date: Java 1.5 (take the JRE)

By the way don't exect immediate connection. LW can take some time. Leave it to settle for a bit. Even try manual connect. Tools>Options>Connections & untick option box for immediate startup & press Apply button.
Then after opening leave it for 15 mins & then go to menu File>Connect.

Do this simple test for us. Using your browser go here: http://www3.limewire.com:6346/ The page should say ‘Test Page was a Success’. What happens when you go there?