Q&A with the Seat Expert

Which airline has the best recline in business class:
Avianca – Mexico City to Bogota @ 350pm or Mexicana – Mexico City to Buenos Aires @ 10pm?

We have a question regarding carry-on luggage on Lufthansa Airbus A340-600, seating in first class ROW 2D and 2G. We noticed that there is no overhead storage or seat storage for these seats, where would our carry-ons go?

Is seat 39A on an British Airways 777 a window seat, or is it situated behind the last window?

We are a group of four (2 couples) travelling from San Francisco to Hong Kong via Singapore Airlines on the Boeing 777-ER300. What’s the best seating plan for economy?

Also, do you know if I can use United Mileage Plus miles to upgrade?

I am trying to figure out what is the maximum sized bag that I can carry on to a regional jet (embraer, etc.)?
Is there more space under the seats or in the overhead bins?
Is there a maximum size that will fit as the 22 x 14 x 9 does for bigger planes?
Can a person take on 2 bags, one small enough to fit in the overhead, and one small enough to fit under the seat, or if you have two bags, you will always be asked to gate check one?

Could you please tell me if there is a difference in the amount of incline-recline (how far the seats go back) of the seats in economy and premium economy on the Virgin Atlantic Airbus A340-600.

I have tinnitus. I will be taking a 5 hour plane ride from Oakland, CA to Honolulu, Hawaii on a Boeing 767. What area of the plane would be the best place for me to get a seat?