Can you give these details please  
System details - help us to help you (click on link). 
Here's some things to consider trying in the meantime ...
(a)  
Tip: Purge the Downloads Queue!
(b) Defragment all your Hard Disk Drives.
(c) Keep shares not much more than or below 2,000.
(d) Try deleting your LW Preferences folder whilst LW is 
closed; instructions here: 
Point #2 & 3 in Fixes for Limewire (sample image included at bottom of page.)