2. If you've got the AVG Free anti_virus, there's no firewall included. But some AVG products do include a firewall, so check which product you're using

6. Have a look on the Linksys & see if you can find a model number (eg WRT 54G).

9. Who do you pay for your internet access (which company)?

11. Are there other computers in the house, connected to the internet, besides the one you're using?

Have you made sure that LW's allowed through the windows firewall?