We took my DS at 16 months old last year...I had been a million times before having him but felt the need to research every last thing about what he would or would not like...and I regret it. It gave me a false sense of what to expect. Be prepared to just "go with the flow"! Rides/attractions that were recommended...he could have cared less...he liked things we would have never dreamed he'd like. The very best thing you can do is clear your schedule and let her go at her own pace. My DS was fascinated by the ropes around lines and the trash cans...it made me crazy but when we gave him enough time to explore on his own he eventually noticed all the other cool things at WDW.
We took him on all the Fantasyland rides and the Pirates of the Caribbean, and assorted others. I think he had more fun just chasing bugs and leaves while we people watched. I'm not trying to discourage you!! No way! Just be prepared to do what she wants to do. We witnessed parents forcing little ones on rides...basically to get "their money's worth" (as I heard one mother say) and I felt so bad for them.
There are multiple web sites devoted to WDW information and you can find lots of advice about specific age friendly rides...there is a "planning with children" section on this site under the WDW tab that I am sure can help!
Good Luck and ENJOY!