How do I disable a firewall(s)?

[Andy7]

I'm pretty sure I have a firewall built-in to my isp router or whatever that stuff is, and I'm not quite sure how to disable it. I can't connect to UT online servers, not to mention the LAN problems I had with AoE and WC3. I also verified that the important ports were closed (not a good thing for internet play) by using telnet, with the guidance of windows help :p. So, can any comp whiz here help me out? I don't really wanna call up my isp..it's a hassle..

Thanks :D

[Andy7]

Oh yea, forgot to mention how my comp freezes up at the UT server screen once every time I load the game, so I have to alt+tab and wait about 20 secs then fullscreen it again..:(