On our first visit with my kiddos (2009), we headed right to the parks after checking in at the hotel. It was a short day, but crowds were low and we had a blast. We hit DCA first, and within seconds of walking in, DS (then 4yo), got to meet Mr. Incredible and Frozone. He was floored! We saw the Pixar Play Parade and had a really nice evening.
I'm sure you'll get to see some characters out and about, which will really get the magic started. Depending on what your DD likes, you could try to see some princesses, get a set of Mickey ears, stroll down Main Street, look for hidden Mickeys, just take your time and absorb it all.
You'll have a great time, even on a short day.