This is a Good advice for other newbies like me trying to tweak a new Broadband Router/Firewall
I noticed a Major Bandwith performance decrease right after I upgraded my good old Linksys BEFR41 to a Netgear FR114P.
It took me couple days to find out it was only a bad MTU setting.
Make sure you set the router/firewall MTU to its optimal value.
I found a good article which explain out to do it.