iMac 10.6.3 won't connect wifi!!!

[AHQK]

So I have done just about everything to connect via Airport. All was well till last week. I think a system update seriously screwed up my airport. I have reset the router numerous times. I have reinstalled 10.6.3 (It was at 10.6.8). I have deleted system calibration folder. Tried new locations via network settings. Disabled Iv6. Requested new DHCP ID. I have done everything!!! Save a factory reset on my router which I can't because it's thru the cable provider. Everything else in this house connects fine. 2 iPads, Droids, Xbox. My computer was fine and then all of a sudden it can't connect. It shows it connects to ISP but not internet. Also give the quote: "Self IP address 225.... and will not connect to the internet" What am I going to do. And ethernet cable is out of the question. The router is downstairs.

 

[BrianBaughn]

Understand about the ethernet cable, but for testing purposes does it connect that way?

 

[AHQK]

Not yet will do