Internet connection problems

I've been having a very annoying issue with my internet connection while surfing, downloading and playing online Halo...the connection periodically drops. On safari or IE it says that it couldn't find the server, typical message when the connection is lost. It is usually temporary and after a click or two finally loads, but when playing Halo it destroys my ability to play.

I've reinstalled system software, no effect, I'm also having trouble with disk doctor as it won't recognize my hard drive...any thoughts on that?? (Anti virus does)

I'm running a MDD 1.25 dualie with 768MB ram, panther 10.3.2, all updates installed. Everything is pretty much stock. It has just started running badly, I've played for quite a while seemlessly.

Is it likely that it's a comcast cable problem? They haven't been helpful, saying it's probably a hardware/software issue. Is there something specific I need to tell them?

 

BTW

I should mention that I am connected through an airport extreme station which is connected to the cable modem. This computer is actually connected by cable, not wireless.

 

thank you, I'll try that tonight.
I appreciate your quick attention.