Fairytale summaries graciously provided by PociandSmith:

link (here there are 10 tales, but only 6 are about Disney Princesses) Cinderella, Snow White and the Seven Dwarfs, and Sleeping Beauty

link Beauty and the Beast, but there are also some of the ones mentioned above

link The Legend of Mulan (read the summary, not the poem)

The results for this poll will be based on comments, not the poll itself!

I chose Sleeping Beauty because it's only a tiny sliver of the original fairytale. Of course, there's the tiny detail that she's supposed to get raped and have two children WHILE SHE'S STILL ASLEEP, but then there's also the fact that the prince is already married, and his mother wants to eat Sleeping Beauty's children.

The credits themselves say that Sleeping Beauty was based on Perrault's tale, and the movie is very similar to that version.
The original tale of Mulan is more a framework of a story than a story itself, but many things are different- Mulan has siblings (including a brother not old enough to take his father's place,) her parents seem to be in on the act, she is gone twelve years, and Mulan is never discovered but reveals herself after coming home from the army to all her fellow soldiers. The only thing that really remains that same is Mulan matures and goes through a period of great maturity (also the symbolism of twelve years) and that the Emperor offers her a position but she returns home instead.

Yeah. I think she was older in the poem, was not caught until after she served her many years, did not have feelings for her general. There really is not much of a story to the original poem. Oh, there is no dragon, and did not leave for dishonour.

She actually did end up marrying a general. Take a look at the summary I posted!

Or Beauty and the Beast.

There are a few really big differences compared to the original tale.

What rhythmicmagic said