go to Download Java Runtime Environment 1.6.0.12 - FileHippo.com and download the latest java runtime environment, reboot, then try to open it again, if not then download this version of limewire http://www.filehippo.com/download_limewire/4669/ because a lot of people are having a lot of problems with LimeWire 5.0 (e.g very few results in search and skin problems).
Sometimes the newest version of software isn't always the best