Man, how can anyone just pick one... I'm a huge splash mountain fan, I broke my Disney cherry on that ride (Funny story, it was 10 in the morning, on March break, and my girlfriend (now my wife) said "You don't get wet if you sit on the front!", and we went on it, and I was amazed, the song was in my head all night... I get misty when I hear that ride through on Mouseworld Radio...
But for Magic, I'd say Peter Pan, there is something so magical about that ride, it really gives you the illusion of flying, going higher and higher then ascending back down again.. the dramatic lighting, seeing the lost boys, and the indians....
I would have to say either of those two rides do it for me!! I agree with some other postings on here, that just walking down Main St towards the castle is delightful... simply delightful!!