OK, to answer your questions, the exact model of modem is CGN3, and yes, I did try to move ports on the modem but not the computer. I only have one ethernet port on my PC that I can see so that is not an option, but moving to different ports on the modem has the same result - no connection. Also, the modem's ethernet cable is plugged directly to the back of the computer, and the modem is plugged to the wall outlet, not an extension.
So, now that I have switched back to yellow cable (the one producing green light was from an older model modem cable I had lying around), I have a yellow flashing light again, instead of green. The other two items are credit card machines for my business that are flashing green. No other choice of cables for those.
I am thinking out loud here: If there was a problem with any of the cables/hardware, would it not also act up on the wifi connection? I am able to access internet just fine if I connect via the wireless, it's only when I try to use the wired connection that I have the "No Internet Access" message.
Aside from all this, the rogers tech mentioned software issues. I kind of doubt it because everything was just fine until after the storm. I have no idea what kind of software things to look for.