Yes, the title would have been confusing for someone who's never watched the series or doesn't know what it's about. I think she commit suicide because she didn't want to be considered a threat to her nephew Li Long Ji's throne. Frankly, I thought that was really unnecessarily tragic, but then again, given what her mother had done, I guess I can understand the logic.
One of your parents has the same birthday (different year, of course) as TGQ?
TGQ isn't an old man. He's just (much) older. Yes, it's a shame more people in our generation are not familiar with him. Just make SGYY a required part of the school curriculum and I think that will change very rapidly.