I am not sure there is any way you can ensure what type of table you are given. You may be able to tell them you will wait for a window table to open up, but I'm not even sure you can do that - some places don't allow it.
I will have to ask as well in a few weeks I know the last time we went once we had a window and 2nd time inside more but i think it depends on what is opened after you take picture...
1) I don't remember a window table for three.
2) That would put someone in the servers walking aisle.
3) Of course, things could have changed for window table sizes.
We asked when we checked in, and they gave it to us. We were also the first lunch seating. We were a party of 6. I think there were tables of 4 near the window. We had the table that the princesses came to first after they were announced, it rocked!