Having problems with Lynbksys Router

[EvB]

At the moment, I'm trying to put my new computer onto the internet.  I can't seem to gt it networked no matter what. I called my ISP (Comcast) they put me over to Lynksys (my router brand) and after keeping me on hold while the scarified yet another goat to Ghonish - this guy "Shawn" (Yeah, and my name is Salome) they told me they won't give me tech support for a perfectly good router becuase it over a year old (HORRORS!  an 18 month old router!) and I have to pay another $30 and then they PROMISE they will tell me how to  make it "like new"

I'm loosing work time, school time and santy trying to do what SHOULD be obvious.  Configure the PCs - stick the cables where they belong, and boot up. 

No dice.

Any ideas?  Or do I have to help play for the goat heard?

My router is a WRTP54g  which at the moment I am used WIRED - not wireless.

[Pirate King Atomsk]

Make sure you do a process of elimination to make sure the router is definitely the issue, if possible.

Now, if you're sure it's the router, you can reset the connection settings on most Lynksys models (to my knowledge) by pressing a small indented button with a pen or pencil tip or something thin enough to get inside. This button/hole is usually on the bottom in a corner. After doing that and reconfiguring your router, if it still does not work, I'm not sure what to say except possible hardware issue, or, maybe it's something else you overlooked unrelated to the router. 

Edit: My mistake, I was thinking of Netgear, but I'm sure Lynksys has the same type of button somewhere on it.

[EvB]

They do - it does - and that's not it.  Nor is it the router - NOR is it anything with the chords, the ports, nothing! 

I'm going to update the Lynksys firmware for shits and giggles - but my final suspect (so far)_ is that some setting on on of the PCs has MAC addresses locked. 

[EvB]

Well - Dammit - it WAS (mostly) the router.  I'm still not there yet - the PC's don't connect to each other but they BOTH connect to the internet.  Three solid days and $100 for a new VOiP router - and I can see some light at the end of this VERY annoying tunnel.