Movie star Jennifer Aniston of the U.S. arrives at the Australian premiere of her latest movie 'The Break Up' in Sydney June 5, 2006. (Will Burgess/Reuters)

LOS ANGELES - Supported by real-life romantic splits and hookups, Jennifer Aniston and Vince Vaughn's "The Break-Up" pulled an upset over the mutant world of the "X-Men."

"The Break-Up" debuted more strongly than expected with $38.1 million to take over as the No. 1 weekend movie from "X-Men: The Last Stand," which slipped to second place with $34.35 million, according to studio estimates Sunday.

Aniston's split from Brad Pitt last year and her reported romance that began with Vaughn while filming "The Break-Up" helped keep the movie in the public eye.

"They're always in the press," said Nikki Rocco, head of distribution for Universal, which released "The Break-Up." "Every time you turn around, somebody's talking about Jennifer, or Jennifer and Brad, or Jennifer and Vince. It's not why we made the movie, though."

"The Break-Up" pulled in about $10 million more than Rocco had expected.

After putting in a record four-day debut of $122.9 million over Memorial Day weekend, 20th Century Fox's third "X-Men" movie tumbled. The movie's domestic gross dropped a steep 67 percent from its Friday-Sunday haul the first weekend.

Still, "X-Men" raised its total to a whopping $175.7 million in just 10 days, a mark it took "X2: X-Men United" 18 days to reach. Bruce Snyder, head of distribution for Fox, said the film should top out at $240 million to $250 million, beating the $157 million take for the first "X-Men" and the $215 million return for "X2."

The huge decline in the second weekend was typical given how many people saw the movie over the holiday weekend, Snyder said.

"I'm not shocked at that drop," Snyder said.

DreamWorks Animation's cartoon comedy "Over the Hedge" held up well, placing third with $20.6 million for a three-week total of $112.4 million.

Sony's "The Da Vinci Code" was No. 4 with $19.3 million, lifting its three-week domestic gross to $172.7 million. Worldwide, the Tom Hanks film adapted from Dan Brown's best-seller has grossed $581 million and should hit at least $750 million globally, said Rory Bruer, Sony head of distribution.

In its second weekend, the Al Gore documentary "An Inconvenient Truth" went into wider release and broke into the top 10 with $1.33 million, even though it was playing in just 77 theaters.

Released by Paramount Classics, the film averaged an impressive $17,292 a theater, compared to $12,410 in 3,070 cinemas for "The Break-Up."

Chronicling the former vice president's campaign to educate people about the perils of global warming, "An Inconvenient Truth" expands to more theaters over the next two weekends.

"It's breakups and global warming that I think really are interesting people now," said Paul Dergarabedian, president of box-office tracker Exhibitor Relations.

Overall business rose slightly, with the top 12 movies taking in $128.9 million, up 1.6 percent from the same weekend last year.

After an 8 percent drop in movie attendance last year, Hollywood is positioned for a solid summer. Attendance is running about 1 percent ahead of last year's, with what looks like a solid crop of blockbusters still to come, including this Friday's animated comedy "Cars," from Disney and Pixar, and the Warner Bros. adventure "Superman Returns" on June 30.

Estimated ticket sales for Friday through Sunday at U.S. and Canadian theaters, according to Exhibitor Relations Co. Inc. Final figures will be released Monday.

1. "The Break-Up," $38.1 million.

2. "X-Men: The Last Stand," $34.35 million.

3. "Over the Hedge," $20.6 million.

4. "The Da Vinci Code," $19.3 million.

5. "Mission: Impossible III," $4.67 million.

6. "Poseidon," $3.4 million.

7. "RV," $3.3 million.

8. "See No Evil," $2 million.

9. "An Inconvenient Truth," $1.33 million.

10. "Just My Luck," $825,000.