"Upgrading" your account usually means you pay the provider more money in return for more bandwidth and privileges, but this is more often meant for a business than an individual, and is rather expensive in turn.
It's just barely on the acceptable side of 'scam', I think. They put up a security bulletin full of specious reasoning and block all kinds of ports and services unless you pay extra cash for a business account.
Mine, for instance, isn't too bad. They block port 25 in AND out (email), port 80 in (http), 20 & 21 in (FTP), and a handful of other service ports. They limit my upstream bandwidth to a measly 45 Kbps. BUT, if I pay a lot more for a business account, then I can run whatever servers and use whatever e-mail services I want, with a much higher upstream bandwidth. 45 Kbps is barely enough to run an Unreal Tournament server, and not even that at times if I have more than one outside player. =(
Did removing the router + rebooting the modem work?