More often than not, these types of errors are Java related. If installing Java 1.5 didn't help, might I suggest you install Java 1.4.2 instead to see if it overcomes the issue. Java 1.5 runs better on some people's systems whereas sometimes Java 1.4.2 runs better on other people's systems.
Uninstall Java using your Add/Remove Programs control panel. Then Downld Java 1.4.2 but don't install it over the internet. Instead, save the installer to your comp., then install it. See how that goes. You can get a link for Java via this link here: Fixes for Limewire (If that doesn't work then try deleting the LW preferences folder.)