This line only shows up in the dub, but it makes the whole movie all the more awesome.
Chihiro: (in a matter-of-fact tone) I think I can handle it.
To explain, Chihiro's dad mentions that moving to a new neighborhood might be a little intimidating and that it's okay to be a little scared. Chihiro's taken on some of the most frightening creatures in the Spirit World, the normal world doesn't stand a chance.
Haku calmly standing his ground when Yubaba flies toward him, raging about her missing baby and breathing fire in his face.
Chihiro sticking her entire arm into Haku's toothy maw to give him the medicine, and then holding onto his head for dear life until he swallows it, while his lashing tail trashes the rest of the room.
Chihiro's entire reaction- or lack thereof- to Haku in this state is simply amazing. It really speaks to her badassery. She saw her crush and rescuer turn into a roaring, thrashing, bleeding terror of an animal and completely ignored it to do what needed to be done... Namely, opening up his horrifyingly deadly-looking jaws, gingerly inserting her whole arm past his giant fangs and into his throat to administer life-saving medicine, and then holding on to his jaws for dear life as he starts convulsing and destroying the room around her, all whilst maintaining a fearless, determined expression on her face. Holy shit.
Yubaba's son standing up to his mother for Chihiro's sake.
"If you make Sen cry, I won't like you anymore!"
The movie in general. It's considered one of the greatest animated films ever made and in Japan, it's the highest-grossing film of all-time, even beating out Titanic!.
Haku flying Chihiro back to the bathhouse at the end and his ensuing transformation after she figures out his name.
The cleansing of the River Spirit, which joyfully flies around the room and out an open window afterwards.