When Melinda Wedde took her daughter Zoey to see "Frozen" for the second time in January, she faced a challenge: Convincing the four-year-old not to sing every song out loud in the theater.

Walt Disney Co.'s animated musical has been a surprise blockbuster. Despite opening before Thanksgiving, it beat a dozen new entrants to become the most successful movie of the holiday season. A week ago it enjoyed the rare success of ranking No. 1 on its sixth weekend playing nationwide.

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