Ariel

In my humble opinion, Ariel is the most gorgeous of all the Disney princesses. Her hair is her best feature, and it really makes her stand out from the rest of them - you don't see too many 'fiery redhead' Disney princesses!
As well as her cute looks, she has independance, strength and spirit and she knows how to have fun! Her best friends are Flounder, Scuttle and Sebastian.
She can definitely be serious, though - standing up to a father like King Triton can't be done too lightly! She decides to see the sea witch when things aren't going her way and despite a bit of pushing from Ursula, it's Ariel who ultimately decides to exchange her beautiful voice (Jodi Benson was an inspired choice) for human legs.
Ariel falls in love with the handsome and brave Prince Eric on sight and decides to do something about it.

Probably the most innocent of the princesses - excluding Snow White and such - Ariel is headstrong, seeming a little younger than many of the others (though her age, 16, is about typical of the princesses) and sweeter and charming than most other characters which come to mind. She's tough, too, when she wants to be.
Definitely a gorgeous person and a true heroine. She's even inspired me to brush my hair using a dinglehopper!