If you're using LW 4.4 or later then re-installing LW will uninstall the previous version. It uninstalls it at the beginning of the installation process. Uninstalling should not be done using the Add/Remove progs control panel. If you simply want to uninstall LW, go to Start Menu > Programs>LW>Uninstall.

If still having problems, try deleting your LW Preferences folder whilst LW is closed; instructions here: Point #2 in Fixes for Limewire (sample at bottom of page.) But if you have LW 4.10 & it is your 1st version, then do step 3 in the link.