I remember being frightened by the Evil Queen in "Snow White" as a girl. But when my then three-year-old begged to watch it, I agreed to let her watch this classic Disney movie. Like me, she was frightened by the scene where the huntsman is supposed to kill Snow White, and had a nightmare about the Evil Queen. She even had to put the video in the freezer before she could sleep that night!
However, when my second daughter,who is MUCH less sensitive, saw it, she loved it and was enchanted by the story. She was only 2, and soon after we went to Disneyland. When she saw the Evil Queen standing by the castle, she ran to her sister, then 4, and told her, "Cover your eyes! Evil Queen too scary for you!" and then hugged the character and told her she loved her.
The moral? You know your child. Make decisions accordingly. My oldest was afraid of King Triton, Maleficent, Jafar, Santa, Ronald McDonald. My youngest is afraid of nothing.