I took my 22 mo son last week, and honestly don't know if I would do it again. The ride really does move fast. Even with my arm wrapped firmly around him, he spent most of the time with his head ducked forward into the car. I was mostly worried that he would bang his head on the lap bar at some point.
When we exited, he had a look on his face that somehow combined happiness and exasperation. He didn't cry or complain, so I tend to think that he enjoyed the ride. But he's still a little too young to communicate any feelings of enjoyment.
I doubt you would do your child any harm in taking her on the ride, but don't expect the type of reaction that you'll get when she meets Mickey or Minnie. If my own experience means anything, I just don't think a child under 2 has any emotional basis for really developing an enjoyment for this type of ride.