I think the Crystal Palace would be PERFECT!!!!!
Try to get an earliest seating PS (8:05am)- call exactly 60 days out at 7am. Maybe the CM's can arrange something special. Make sure to bring her a birthday crown.
You will be able to get great pictures of her in front of the Castle and probably get on the first Dumbo ride of the day!
Plan an early hotel break, so she doesn't get over stimluated and then head back to the parks in the evening.