Since you couldn\'t use BitTorrent to download, it seems that there is some extremely restrictive firewall somewhere between you and the internet, not necessarily (or exclusively) on your local computer.
You are not, by any chance, connected through some sort of (semi-)public network as found, for example, at schools or at work? These tend to block any sort of traffic that isn\'t strictly required for the purpose of the networks existance, and if you don\'t have access to all the firewalls and routers, there is no way of poking through.
Also, some ISPs are blocking ports or entire protols (UDP, in this case), so you might try to contact your ISP to see if they will allow the connection and if not, you need to switch ISPs.