Wow there is so much information here i can't take it all in at once...
Give me a minute to process the vast quantity of details you gave to allow anyone to help you and i will be with you shortly...
Yes, my firewall is off, yes, the ports are forwarded. Strangely enough, I have tons of friends connecting, I'm the only one that cannot, as I'm on a different PC.
I just remembered, last time I encountered this problem my IP was wrong when I had ports forwarded. That's the only thing I can come up with for you folks.