Alright,
Sounds like we made some decent progress here.
You know, I didn't even think about the Internet Options, connections tab
Bastard - Good call.
Generally, you're not going to use those type settings unless you're using a modem. Since you stated you're using cable for Internet connection, I gave you're IT guy too much credit. There is no need for those settings with a broadband connection that are used today.
I think you may be good to go now.
Give us an update after a couple of days to let us know if it works like it should.
joe