When Lisa and I travel together on one USA + one UK passport, man and wife, Lisa with ILR, we just go which ever queue is shorter ... on arrival in the UK and on arrival in the USA. Best of both worlds.
On Lisa's first arrival with a spouse Visa, we went to the "non-UK" queue and I would suggest, ElizabethK, that you do. Quite the most friendly greeting I've even had from an immigration officer - your visa is your official notice to them that you're a nive person that the UK approves of, and they'll probably chat you through other things you need to do - "do register for a doctor ... do get an NI number" and they'll be very welcoming.
Was it yourself who posted "is that IT" when you got your visa? You'll end up wondering the same thing as you come into the country.
Have a great flight!