If Limewire is constantly opening when you close it, then you may have a worm.

Take a look at #4 in this post

http://www.gnutellaforums.com/showthread.php?t=41432

Hopefully, though, you just want to open it manually when you turn on your computer! If that is the case, click tools...options...advanced...system startup

Unselect 'Run on System Startup'

Good Luck

Dano