Doesn't sound like normal LW behaviour. Have you checked with your ISP to see whether they've put any forms of blocks on p2p use? And is this only happening with LW?

When did this start happening? Did you install any other softw around the time this happened such as other apps or OS updates?

Whilst LW is open make a note of all your settings. Then quit LW, & then delete your LW preferences folder called .limewire & found here: C:/Documents And Settings/your_username/.limewire

Now try opening LW again. Leave it on for up to an hour to see how it is. Don't do anything with LW during that time. See if connection quality improves. If not, do this test: Bug Report instructions & sample image & post back whether your result is true/false.