How do I change my port settings?

I have a Belkin Wireless Router and it doesn't let me play some games online (Unreal Tournament, Sid Meires Civi Revo) on my PS3. How and what do I have to do?How do I change my port settings?
I dont have access to a belkin router but you can probably find it by looking at the manual or online help. In a linksys its a section called applications and gaming. Just log into your router and look at all the screens. There should be one that allows you to enter port mappings. You will need your PC's IP address. Go to start then run and type cmd and hit enter. Then type ipconfig and hit enter. This will display your IP address. You will want to open up the ports for your game and point them to your IP address. Keep in mind that if your games stop working your IP address might have changed.