Netstat -a How do I terminate those connections?

Hi

I am having tremendous problems with my internet. After just a few minutes when restarting my modem & router (I have Virgin Cable broadband) the internet is at a speed of just above 4Mbps on a supposid 20MB connection, the internet latency goes from between 30-40 to over 900 sometimes upto 2000!

I called Virgin who asked me to do a netstat -a on my "dos prompt" on my mac by typing in cmd (god I hate it when they don't support any other OS from windows!!!) from which the results showed there were over 16 IPs with active connections running, they then told me that's the problem and to contact Apple to close the connections which are active "within the computer hardware".

Now, I don't know an awful lot about the terminal interface in Mac and I certainly can't find a simple answer in google about how to close off these active connections.

Can someone lend a hand in whether these are active "hardware connections" and if I can indeed close them?! My speed/latency is awful which is making my experience on Modern Warefare2 terrible!! :o(

Many thanks in advance

Ken