It's not wise to use both XP & Norton firewall as they've been known to interfere with each other. Disable XP's firewall & configure Norton using this: Configuring Norton Internet Security

See if that improves things. If not then 1. try deleting your LW Preferences folder whilst LW is closed; instructions here: Fixes for Limewire 2. & if still not good then update your Java to Java 1.5 (see previous link.)