I am decided to sort DPs to Hogwarts Houses. I'll illustrate this article with pictures where each DP best exhibits the traits of house she belongs( Gryffindors do something risky, Hufflepuffs are doing something useful or exhibit frinedliness, Ravenclaws read or explore something, Slytherins are tricking someone or dream about something). Warning: I have some unpopular opinions but I'll try to explain them. This is how I interpretent Hogwarts Houses and their values:
Gryffindors are first of all are brave, courageous, outspoken and risky. They are also often progressive, rebellious, mischievous, playful, adventurous and/or have a strong sense of justice.They are more likely than members of other Houses be athletic and outdoorsy( but not all of Gryffindors are, look at Hermione). Their defining trait is bravery.
Hufflepuffs are first of all extremely people-oriented. They are very warm, friendly, helpful, loyal, tolerant, humble, they enjoy taking care of others and have a need to useful. They are giving and nurturing, they often create material goods. They are less likely to be jerks than the members of other Houses. My favorite Hogwarts House( but unfortunate I don't fit it much).
Ravenclaws highly values knowledge. They are inquisitive, cultured, intelligent and creative.
Slytherins are ambitious, competitive, dedicated towards goals, cunning and resourceful. They care about their public image a lot. If Slytherin holds someone dear, he(she) is willing to do everything for this person. Can be patriotic and family-oriented( some of them). While I dislike all canon Slytherin characters and find them reformed jerks at best, being virtuous doesn't prevent ambtious and resourceful DP from being sorted by me to Slytherin. And being flawed doesn't prevent DP from being sorted to other House because James Potter and Sirius Black had a mean streak and Luna Lovegood was harassed by other Ravenclaws.

Snow White - Hufflepuff

Pretty obvious choice. She is very friendly, giving, motherly and caring. She isn't too proud to work as servant, despite being a princess. She remains optimistic, despite losing comfort and status( no wonder because which neither of this very important to Hufflepuff). True Hufflepuff.

Cinderella-Hufflepuff

Cinderella's defining trait are her tolerance, patience and soft-spokeness. All of these her awesome Hufflepuff.

Aurora - Hufflepuff

Yes, all three classic DPs are Hufflepuffs in my opinion. Sure, they have different personalities but traits this three share make them a perfect fit for this House. We don't know much about Aurora but everything we know screams Hufflepuff to me. She loves nature and is a friend to animals. She is sweet, loyal and obedient. I didn't sort any offical non-classic DP to Hufflepuff(I would sort Anna and Giselle and princess Su from Mulan 2 and probably(!) Elsa but they aren't offical DPs).

Ariel - Ravenclaw

Well, sure Ariel isn't cautious but she her thist for knowledge is undeniable, she didn't only wanted to join human world because of Eric. And you know... I can name the capital of any Latin American country very quickly and the capital of any Indochinese country because I am VERY good in geography and in many other areas too. But I no more cautious or practical than Ariel... So why not?
However, she an excellent fit Gryffindor too, I agree.

Belle - Ravenclaw

Ariel and Belle are rather similiar personality-wise than not to me. They are both Gryffinclaws to me. This combination makes them devoted explorers whose thirst for knowledge leads them to trouble at time. Belle also has some Hufflepuff( such as tolerance and ability to forgive) and Slytherin( such as some arrogance) traits too.

Jasmine - Gryffindor

Most of people sort her to Slytherin because she is resourceful and cunning but I don't think these are here defining traits. Jasmine is impulsive and outspoken for most of time. She doesn't care about her public image, she is mischievous, adventurous and playful. This isn't Slytherin at all. She is also progressive and upredjuiced which is VERY Gryffindor, status means nothing to her. She is so also very willing to leave the life full of luxuries. So she is more Gryffindor with some Slytherin tendencies than Slytherin.

Pocahontas - Gryffindor

Almost the very first things we learn about Poca is that she is risk-loving, playful and outdoorsy which is so Gryffindor. She doesn't want quiet and stable and dislikes Kocoum for being to serious. Gryffindors tend to be fun-loving. She is also progressive and has a strong sense of justice. Concerning her bravery, it's undeniable IMO.

Mulan - Slytherin

Another unpopular opinion. Mulan is extremely cunning, resourceful, ambitious( the reason she remained in army after Shang send her away) and has a strong desire for positive attention and admiration. She is outspoken at times but definetely much less outspoken than Jasmine. She is also somewhat secretive because she never tell Chi Fu what she thinks about him. Sure, she risked her life to save her father but it's still very Slytherin because Slytherins are often very family-oriented( even Malfoys whom I can't stand). This Mulan's act isn't as selfless as many people say because there is no parents that would to survive their kids. I know it because I am extremely to afraid to lose my elders and I am very awared that this is selfish. I also know that my elders would never want me to risk my life to save them. So Mulan's selflessness is highly exaggerated. Probably she also thought that she is more likely to survive the war but this is again pretty Slytherin. Mulan has some Gryffindor and Hufflepuff traits though. But I still think Slytherin fits her the best! And she is wearing a green armor!

Tiana - Slytherin

I don't see her as Hufflepuff at all, despite being hard-working( her hard work looks like dedication to goal rather than nurturingness like in Snow's case). Tiana is very ambitious( her Almost There song proofs it), she has leadership skills, she likes luxuries and there is some vanity in her too. She can seem somewhat cold to strangers as opposed to how devoted she is to her father( Slytherins are often have cold facade). Some people say that she isn't Slytherin because she didn't agree to destroy Naveen's life but by that logic only ruthless and unscurpulous monsters belong to Slytherin. I can't imagine any DP destroying other's life without remorse. I don't think that Tiana really fits any other house but Slytherin.

Rapunzel - Ravenclaw

Rapunzel is very inquistive, multitalented and creative. She doesn't only shows to hold books during the opening song but also visited the library during Kingdom Dance and really enjoyed exploring maps. However, she is so well-rounded that would also be an excellent fit for Hufflepuff, Gryffindor and even Slytherin too.

Merida - Gryffindor

She is very risky, athletic, mischievous and fun-loving. Also impulsive and reckless. And not all reformed jerks belong to Slytherin!