Yes. I don't know. Definitely not. Probably (but we never reset them)
1) Playing with the voice volume doesn't seem to affect the problem, whether we listen to the show on the TV audio, or send it to my Bose wave radio.
2) Yes, it goes into screen saver mode if it receives no user input after several hours. But any remote action at all brings it back.
3) No, it has no internet connection whatsoever.
4) We have not messed with that menu since we bought the TV. Even then, we only used it to alter the color balance and the sound tone.