It a virus if you have AVG anti virus Do a full scan on your pc that is the only way to stop lw from re-opening.But if you dont have a avg i will give you link for it.
AVG Anti-Virus Free Edition - Reviews and free AVG Anti-Virus Free Edition downloads at Download.com
Like fore say this little worm that many people get it is a worm that will mess with your head a little what it do's it makes your Lime Wire Pop open ever five seconds.The Best thing to do when that happens is Go to Download.Com
And get AVG Free Anti virus it is a free program and will get rid of that nasty worm that most people complain about.Here is a link for AVG.