What cables to use.

I’d go HDMI but with the TV as the source, it isn't going to matter that much. 

HDMI.

May or may not make a sonic difference over optical (depends upon the quality of the TV/cable provider), but you will be good to go with any improvements down the line.

Think they are around the same price, so HDMI.

If you shop Amazon or Walmart and would like something inexpensive look @ Monoprice HDMI’s.

This said, I'm not really into TV but the Monoprice HDMI I use to connect a DVD player works fine (picture/sound) with our TV.

DeKay

@dawg007 

You’re in the right place, sir. Dekay that answered you is a respected member, I trust his take on it!

In the end of course it’s your preference.

Nice family picture, enjoy!

Optical cable will outperform hdmi in long distance application. I have 30ft long hdmi cable connecting my main TV with smaller TV in my tool room in my basement and the quality is pretty low. When I tried 5ft hdmi connection just to check difference,  it was significantly better. 

15’ should not be a problem for a decent HDMI cable.

I’ve used a 30’ Monoprice a few times to directly connect our Internet modem to the cable box (usually run WiFi, but it craps out from time to time) and it worked fine.

This said, our previous and current TV cap out @ 1080P, and like I said I’m not picky about TV (it just needs to look/sound OK).

DeKay