If you're in F, you should be able to select your seat already. You'll need your BA PNR - a six-character alphanumeric string. Then visit http://www.ba.com/mmb to choose your seat. Note that seats 1A/K are blocked for BA Gold and OW equivalent until 72 hours (approx) from departure.

You're unlikely to get your spouse upgraded, but stranger things have happened. Don't go expecting it, though - BA only upgrade when needed, and value status passengers over non-status...

A warm welcome to FT as well! ^