Windows Defender doesn't have a firewall. But Vista does, & so does Norton 360. If you run 2 software firewalls together then you'll have problems with them conflicting with each other & possibly leaving you less protected. So you should turn off the Vista firewall: Windows Vista Help: Turn Windows Firewall on or off & then configure the Norton firewall to allow LW: Configuring the firewall feature in Norton 360

This link might also help with configuring Norton: http://www.gnutellaforums.com/226610-post6.html

Ok, to delete your preferences folder (which is named LimeWire), you'll need to look in this location: C:\Users\your username\AppData\Roaming\LimeWire

And before you can find that folder, you'll need to make sure that you're able to see hidden files & folders (the preferences folder is hidden by default). Grandpa shows you how to to show hidden files & folders, and how to find the preferences folder here LimeWire Pref Folder in Vista

Once you find that folder named LimeWire, you'll need to make sure that the program LimeWire isn't running. LW needs to be completely closed, otherwise deleting the prefs folder won't help at all. So, shut down LW & then go to task manager (Control+shift+escape) & if there's a LW process running - click the option to end the process.

Then delete the whole folder named LimeWire. Restart your computer & then restart LW.

If deleting the preferences folder doesn't help, you can try replacing the gnutella.net file - it's just a file with addresses of hosts to connect to. It's inside the preferences folder. The help thread has links for downloading a new file...you just need to download the file, save it, delete the old gnutella.net out of your preferences folder & then paste the one you downloaded into the preferences folder. So you just replace the old one with the new one. But you need to have LW completely closed before you do that, or it won't work. Once you've replaced that file, restart LW & see how you go.

Otherwise, you need to tell us the model of the Netgear. If no model number's showing, turn the router upside down & have a look underneath.