Hmm, I assume you see a small brickwall in front of the globe in the left bottom corner of the LW window.
That measn LW is blocked by a firewall (could be the XP built-in one if your OS is XP, a firewall in your router - if you use one, or any other firewall which comes with a security software such as Norton Security - if you have one installed)
To get rid of it, and consequently rid of the pop ups you'll have to read here and follow the suggestions made:
http://www.gnutellaforums.com/showthread.php?t=51361
The fact that your pc freezes after receiving several pop ups could be related to a low RAM........though that's just a guess.