We stayed at POR this past April and it was ok (I know a lot of people are crazy about this resort) but for DD we liked Pop better

I was really hoping to try AoA this Sept but when I booked
free dining was not being offered for their regular rooms - AoA looks like it would be awesome for little kids!
I would definately book a character meal - different places have different characters so just check which one has your DD's favorites

In '08 we did Crystal Palace our first day at MK and it was so much fun - Pooh, Tigger, Eeyore and Piglet were really funny and spent a good amount of time with us.
On the day we are planning on watching fireworks we go to the parks later in the day. Usually we go to DtD in the morning, go back to the hotel (swim, nap, lunch) and then go to the parks. Same goes for the day we catch our favorite parade - Main Street Electrical Parade
Since everything is new to you I would find a map of each park and see what your DD might like to do. Check height requirements, show times, you can even look on
YouTube to see the actual rides - some might be scary to one kid but not another.