You've already seen What A Girl Wants -- as the Princess Diaries, as Cinderella or in some other incarnation. This is a fairy tale, complete with a fancy ball and a prince, only the happily-ever-after aspect involves a father-daughter story, not a prince and a beautiful maiden. Freud's contribution to the screenplay is not credited.
What A Girl Wants is one of those clumsy attempts to marry a sweet tale with huge box office, and it will work. Although the movie looks derivative to these old eyes, it is exactly the sort of confection that little girls adore. Adore. However huge this one will be in theatres, you can count on twice as much in video sales. If you care about that sort of thing.