Just wanted to chime in and add my very short thoughts: This is is most gleeful I've ever been coming out of a Disney feature in I don't know how long. I enjoyed Tangled, though thought it left something to be desired - especially in the music department ("When Will My Life Begin" and "Kingdom Dance" aside) and Wreck-It-Ralph was awesome, but it felt like it was shying away from the most critical elements that made Disney, well, Disney (music, magic, a sense of innocence).
Frozen, however, feels right at place as the next hit alongside classics from the 90s. The characters are amazingly animated and written, the story has a couple of really surprising twists and the score and songs - My, my. I thought I'd never feel like I felt during the 90s again but then Let It Go started. I always assumed my love for past tunes was heavily reliant on nostalgia but now I know I was just waiting for the right track to play. The soundtrack is amazing and works best within the context of the movie and characters which, in my opinion, is always a sign that the songs fit the piece and not the other way around. As for the critics disappointed by the lack of a classic villain... Sure, I'll give you that point, there was the opportunity to make the Snow Queen truly evil. I, however, enjoyed seeing such a complex character come to life - and the subtext was enduring. The idea of hiding who you are and what you can do is something I bet a lot of people will relate to fairly easily. I'm hitting this one again tomorrow, and is already on my Blu-Ray purchase list.
(I won't even get started on that short at the beginning which had me become so giddy and childlike I was almost embarrassed for myself.)