Hi Ysenia,
My little girl loves Rapunzel too! Currently, she does not visit any of the character meals. However, you can see her daily in the Magic Kingdom's Fairytale Garden. See
here for more information. Pick up a Times Guide when you enter (located near the park maps). The specific meet and greet times will be listed on there.
For princess dining, I recommend either
Cinderella's Royal Table or
Princess Storybook Dining at Akershus Royal Banquet Hall in Norway. I prefer to dine inside Cinderella Castle, but you will see at least 4 Princesses at each meal.
For your son, I'd take him to
Chef Mickey's to see Mickey, Minne, Goofy, Donald and Pluto. There is a make your own ice cream sundae station and the atmosphere is great. You may also want to try
Donald's Safari Breakfast at the Tusker House in the Animal Kingdom. Donald, Daisy, Goofy and Mickey are dressed up in their safari gear and it's great.
Have a wonderful vacation,
Kaylene