Note: With the ports, you're wrong.
Ports go from 1-65534
This decreases your port "Safety" range by at least 34000 ports.
Which is highly significant.
Besides the point, if he's a Database hacker, he would have experience (obviously) so he would know the ports of your server. Which would then be quite easy to hack.
Your best option for a Firewall/Anti-virus is Kaspersky Internet Security 2009.
Despite the fact that it's one of the best out there, it has Anti-P2P connection activities (It cannot be controlled by any sort of Hacker, or program)
I had Mcafee, and somebody hacked my old PC when I DMZ'd my Router (I know, stupid.) and he shut down Mcafee, I was left completely defeated, he had complete control. Eventually I just wiped my OS and reinstalled.