In 1991, she made her motion picture debut in Disney's Beauty and the Beast, in which she voiced the film's heroine, Belle.

Continuing her legacy as Ellie, she also sang the part on the 1989 Grammy-nominated recording of the musical with Jerry Hadley, Frederica von Stade, and Teresa Stratas, conducted by John McGlinn on the Angel EMI label.

A longtime fan of Walt Disney Pictures,[6] O'Hara auditioned for Beauty and the Beast at the age of 35[7] after reading about the film in The New York Times.

[5] In Season 2 of The Legend of Prince Valiant (which starred her Beauty and the Beast co-star Robby Benson), O'Hara had a recurring role as Princess Aleta (who was later promoted to queen).

O'Hara also starred as Venus in the BBC's recorded broadcast of the live presentation of Kurt Weill's "One Touch of Venus" and in tribute to her Belle character from Beauty and the Beast, she portrayed Angela, a character in a fictional soap opera, for Disney's 2007 live-action/traditional 2-D animated film Enchanted.

[9] Despite this, she has reprised the character on two subsequent occasions: the 2018 film Ralph Breaks the Internet[10] and the 2023 short Once Upon a Studio.