My daughter's first trip was in her first couple of months. No, she doesn't remember the day, but she had a great time. It was family bonding time. She even made Donald talk.
She was never afraid of the characters until she started to understand the stories. Then the bad guys scared her. She was afraid of the Beast until I reminded her that he turned out to be good at the end of the story. My son was never scared of any of them.