We have had pictures taken at several resorts. We found a local photographer who does a wonderful job. We try to get family pictures taken each trip. Our favorites have been the Boardwalk and the Grand Floridan. The poly is great too, not sure when you are going but with the construction that might not be the best choice right now. Wilderness Lodge is also beautiful.
I'm not sure if you are doing family pictures too, maybe everyone riding on one of the surry bikes would be cute. I want to do that with my kids when they are older.