You might be able to resolve the problem by just installing AVG, update and then scan, but read link below. Try AVG before BFU.
Try the fix in this thread:
To fix the limewire keeps popping up / no taskmanager bug do the following
There's a virus that causes LW to keep opening up on it's own, there's also one that prevents the options menu from being accessed. Do a virus scan. If your av doesn't pick up anything, try d/loading
AVG free (click on link) update it and do a scan, then follow the prompts.