Cant connect through IP

[cogenmaster]

Not sure if this is the right topic maybe networking would have been better but here is my problem. My wireless router quite working a couple 2-3 weeks ago. It just all of the sudden stopped passing the internet through to my computer which is connected directly to the router. It is a linksys wrt54g or something like that, I am at work so I cant look at it. I have been out of town on buisness the last 3 weeks so I just disconnected it and hooked up straight to my broadband modem. I called linksys 2 days ago and they had me doing some stuff with ipconfig which didnt help with the problem. They asked me to move the router to another computer and test it to make sure it wasnt my computer. I have not gotten around to doing this but I noticed something odd last night trying to play multiplayer games and this is the reason for the post. Up until last night I just assumed the router was bad but now I am not sure. I was going to play total annihilation with my father-in-law and we could not connect over tcp/ip. We have played it alot in the past, been awhile since we played so we just forgot about it and decided to play linksls. We play that several times a week. We could not connect with links either no matter who hosted. While we are trying this we are voice chatting over yahoo and I am surfing the web. Now that I cant connect to games I use to play perhaps my router isnt bad at all. As far as I know nothing has changed on my computer.
I use Norton internet security and I have been for over a year. I guess my question for this long winded post is this. Is there something in windows that would cause these connection errors. As far as I know windows firewall is off but I cant check for sure because when I do widows says it cant start the the service. Well guess this long enough any help would be appreciated.