hey, ive had limewire for over a yr and suddenly i have just gotten this problem. I see the desktop icon, but when i click it the limewire banner comes up then just disappers. Its akward that this is the first time i have had trouble with this. Ive installed the new java like you all recomended plz help ty

Which version of Java did you install? A few people have had problems with the most recent update 1.6.0_01.
Try this version. Use the JRE offline installer & remove your current Java version before you install this one.
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11

You could also delete LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things. If you're not sure of your settings, go through LW's tools > options & write them all down, so that you can reset things later.

What version of LW are you using?