A.,
PAck lots of snacks, waiting in line can be very hard for her, the lines will be long and strollers are not allowed in line, so snakcs to eat in line (things that take time to eat) can be a great distraction.
Start with OUT door rides. They are not as loud and they feel safer. My daughter is 2 her favorite rides are Dumbo and autopia. Most of the in-side rides are VERY loud and I'll tell you this if you spook her once you won't get her on another ride, LOL we made that mistake. My son begged for pirates of the carabian so we did it first and it ruined our whole day.
Also where ever your not sure, go to the exit of a ride and see who is coming out and what are their reactions, if the kids your daughters age are coming off happy it's probably a good idea, if they are crying you might want to skip it.
There is a princess area, I forget what its called but it's up the hill from toon town that is fun, they get to meet and greet the princesses and have story time.
I think the most important thing to remember is that the day is for her, if she wants to ride the same ride over and over again, well.....
Heehee, well that was much more then I intended to write but there you go, there is what worked for us, and didn't.
Hetaher