Hi,
Here are my thoughts:
Whatever park you are going to, make sure that you are standing at the gate to go in at least 10-15 minute before its scheduled to open. Crowds are low then and its nice to see the park without people all over the place. You also get on rides without as long of a wait. We were just there in Jan, and they had eliminated all of the opening shows at the parks, so I would not count on seeing those.
I would also start at the Magic Kingdom. Its really impressive and fun. And if she is a fan of Disney animated movies, she will love this park. I would plan on having dinner at the Castle the first night. Since its her first time here, she wont really want to hop from park to park her first day. Theres so much to do here, you wont get through it in one day.
The Halloween party is fun, no matter your age, although it is pricey because you cant get in with your regular pass. You have to buy a separate ticket. Some people dress up in costumes. The characters are in costumes. You can get your picture taken with Snow White and all of the Dwarfs and Cinderellas glass carriage. The parade is awesome
.all kinds of Disney villains. And get to Frontierland at least 30 min before the parade. The Headless Horseman is awesome.
As for Epcot, maybe Soarin wasnt there the last time you were. It is very cool. Test Track is fun too. Go to the Food and Wine Festival there during the week, not the weekends. Itll be less crowded.
At Hollywood Studios, we love Rockin Rollercoaster. Im also a fan of the veggie sandwich at Backlot Express. I know people complain about the counter service food at this park, but I love that sandwich.
Animal Kingdom ride the safari at different times of the day, youll see different animals. The bird show is funny and if she likes animals, shell enjoy the different birds. My kids are in their twenties and love the Dinosaur ride. Its a Bugs Life is always good too.
Youll be there for a really nice amount of time. I would just try to do all of the rides! Dont worry about if other people like them or not. Give them a try and see what you think. Personally, I always like Sounds Dangerous (I think they are changing the name) and lots of people seem to hate it. I hate Tower of Terror, and others love it. I love Rockin Rollercoaster and Peter Pan
and they couldnt be more different!
I would see Fantasmic. That is the best evening show at WDW in my opinion.
Have a great time! We will be there around the same time as you, but our dates are not finalized yet.