One new release promised a harrowing 9/11 recreation while another offered leotard-clad young actresses, but more moviegoers flocked to Robin Williams, whose comedy "RV" earned the #1 spot at the box office.

The family-friendly film raced to the top of the heap, beating three other new releases to earn $16.4 million and the box-office title, according to early estimates. Williams stars in "RV" as Bob Munro, an overworked dad who promises his family a vacation in Hawaii to bring them together, but opts instead for a road trip to Colorado in an RV (see [article id="1529603"]"Robin Williams To 'RV' Co-Star JoJo: 'You The Man!' "[/article]).

"United 93," focusing on the passengers and crew of the fourth plane hijacked on September 11, 2001, bowed at #2 with more than $11.6 million. The film recreates the flight in real time as the passengers banded together to fight back against the terrorists that took over the plane, and follows the reactions of the victims' friends and families (see [article id="1529291"]" 'United 93' Director Goes For Realism, Vows Not To Mythologize"[/article]). Though it comes up behind "RV" in gross earnings, "United 93" played in far fewer theaters than the Robin Williams comedy, and had the highest per-screen average of any major release. "United 93" earned an average of $6,465 in 1,795 theaters, while "RV" earned an average of $4,506 on 3,639 screens.

The gymnastics-centered comedy "Stick It" bowed at #3 with more than $11.2 million. In the film, a rebellious former gymnast with a criminal record (Missy Peregrym) returns to the world of uneven bars and balance beams and teaches her teammates that they don't have to follow the strict rules of the sport in order to be champs (see [article id="1529438"]" 'Stick It' Cast Tumbles Into Gymnastics -- Neon Leotards And All"[/article]).

Last week's top four were each bumped down three notches under the weight of three new releases. Last week's #1, the thriller "Silent Hill," dropped to #4 this week. Following a mother's frantic search for her missing daughter in a mysterious town threatened by a dark force (see [article id="1528769"]"No Green Screen Here -- 'Silent Hill' Baddies Report To Set"[/article]), the film earned $9.3 million.

"Scary Movie 4" slipped from #2 to #5, earning more than $7.8 million its second week in theaters. The comedy stars Anthony Anderson, Anna Faris, Carmen Electra, Chris Elliot, and Dr. Phil, and pokes fun at blockbusters including "The Village," "Saw" and "War of the Worlds" (see [article id="1528422"]"Shameless 'Scary Movie 4' Has Foam Butts, Alien iPods"[/article]).

"The Sentinel" also took a tumble this week, dropping from #3 to #6. The film, starring Michael Douglas and Kiefer Sutherland and centering on a Secret Service agent wrongly accused of attempting to assassinate the president (see [article id="1529005"]"Who Wants To Kill The President? Star-Studded 'Sentinel' Cast Won't Tell "[/article]), earned $7.6 million.

Rounding out this week's box-office top 10 are "Ice Age: The Meltdown," which slipped from #4 to #7 with more than $7 million; "Akeelah and the Bee," which debuted at #8 with more than $6.2 million; "The Wild," which dropped from #5 to #9 with more than $4.7 million; and "The Benchwarmers," which fell from #6 to #10 with $4.4 million.

Overall, ticket sales were up from the corresponding weekend last year.

Next week, look for "Mission: Impossible III" and "Bandidas" to debut on the box-office top 10, while "Art School Confidential" opens in limited release.

See everything we've got on "RV", "United 93" and "Stick It".

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