My God, I am an idiot! What I have is an Obi202, so that is why I do have two lines into it. I modified my original question and post to say 202 so other people searching will not be confused.
I tried several things, but I think what finally solved it was unchecking the forward to Google Chat, and then enabling it again. So now when someone calls that line, it rings on both my cell phone and the wired phones, as it did in the past. Thanks for your help pointing out my error, and your suggestions as well.