One temptation I (and probably other well-meaning parents) succumbed to was rushing through Fantasyland, seeing a short line for Mr. Toad, and riding it first in the day. My 4.5 year old daughter was bawling even in line because it was dark, screamed through the ride, and we had a hard time getting her on any other dark rides for much of the day. I had thought "it's not that scary, it's a kiddie ride, we'll do it now while it's not a long wait." Big mistake. She had no idea what to expect, so it terrified her.
I think a kid's first few rides should be things they can see what they are going to be riding (i.e. Gadget Coaster, Autopia, teacups, even BTMRR) because it builds the trust that it will be more fun than scary, even if there are some surprises. Some of those dark Day-Gol rides in Fantasyland are intense, especially if the kids aren't familiar with the story.
PHXscuba
p.s. Roger Rabbit is very similar, except that your car spins around as well.