At 2, I'd be surprised if she has any real concept of exactly what Disney World is or any concept of time either. I think it's scary for toddlers sometimes because they're not babies but nor are they old enough to rationalise and figure out the whats, wheres and whens of a situation. I have a two year old girl too.

We're 6 weeks away from our WDW trip but she really doesn't understand anything about the notion of us going on a holiday, let alone the specifics of Disney World, you know? Now she loves Mickey from seeing him on T.V. and she loves looking at our photos from Chef Mickeys - she can't get enough of hearing about Snow White and Cinderella - every single night she wants a "princess story"
So basically I keep any mention of our upcoming trip very simple. A few days ago, after telling her the Cinderella story yet again (!!) I told her we'll be going on a plane in a few weeks to meet Cinderella. For a couple of hours afterwards she was saying "come on Mom, we go plane now, meet princess, c'mon, now'.

Then she totally forgot about it!
So, after that long-winded message I just wanted to say (what others have said too) to keep it simple - just maybe focus on one character and the day of your trip tell her you're going to see where Minnie (or whoever!) lives!
Good luck! Cancel? No way!!
