Welcome home! We have stayed at VGF for the last three years in early December. VGF and GF are amazing for Christmas.
My advice is don't worry too much about a view. They are all pretty good. I would think through whether you prefer upper floors or a lower floor and request that. Some of the standards have a view of the monorail, Poly, Wedding Pavilion and the Golf Course. The other 1BRs have a view of the monorail, the VGF main building, and the back side of the pool. From some of these rooms, you may be able to see Fireworks if you go out on the balcony, get close to the rail, and look to the right. It is a pretty small number of 1BRs that have this, so don't be disappointed if you don't get it. If you want to try, request a pool side, with upper floor. Keep in mind that some of the Grand Floridian hotel buildings will be between you and the castle.
My least favorite views are the lower floors on the golf course side, because the Porte Cochere looms large in the foreground.
My advice is to request whatever you want, but don't tell your family or guests about it. They will likely be wowed by the view wherever they are.
The best options for watching fireworks are Gasparillas (outside patio), the boat dock, and Narcoosie's outside deck (reservations at Narcoosies needed for this one). These three are great because the music is piped in, and the fireworks are much better with the music. You can also see the fireworks from the beach area, but no music is available AFAIK. There is no music available in the rooms.