Try deleting you .limewire folder and see if that helps.
Fixes for Limewire when LW isn't operating as it should
Never mind I see you already tried that. Have you tried uninstalling then deleting your limewire file in C:/Documents and settings/user name/application data.
I see you have tried allot of things but it seems to me it has to be a preference settings problem due to the fact that it is carrying over to every version you install. Be warned when you do this you will loose all of your current incomplete downloads and I do not know that it will fix your problem either. Like I said earlier there was a prior version that had this problem but the next version fixed it for me.
Hope it fixes the problem if it doesn't I do not know what else to suggest.