John Lithgow stood motionless in front of a wall of Willem de Kooning’s paintings at the Museum of Modern Art last night.“I am thinking of which one I am going to steal,” said the Tony award-winning actor, whose many credits include the voice of Lord Farquaad in “Shrek” and the Trinity Killer Arthur Mitchell on the “Dexter” television show.Lithgow had two words to describe what he thought of “de Kooning: A Retrospective,” a sprawling exhibition that brings together about 200 works from public and private collections.“Love it,” he said, moving off to examine ribbons of color.MoMA’s survey of the Abstract Expressionist’s career, spanning the years 1916 to 1987, had patrons ladling out praise for curator, John Elderfield, who spent six years putting it together.“To see all these paintings under one roof is incredible,” said John Berggruen, San Francisco-based art dealer. “It’s a once-in-a-lifetime opportunity.”The opening party on a sticky night attracted hundreds of guests, including actor Owen Wilson; artists Glenn Ligon, Dana Schutz and James Rosenquist; New York City Transportation Commissioner Janette Sadik-Khan; art dealers Tony Shafrazi, David Zwirner and Jay Gorney.Big lenders to the show included David Geffen, Steven A. Cohen and Henry Kravis. The bars in the cool lobby attracted hordes of men in porkpie hats, bow-ties and plaid shirts and women in low-cut dresses with large colorful tattoos.MoMA’s entire sixth floor was taken over by the exhibition, which runs Sept. 18 through Jan. 9, 2012. The appraised value of the works added up to about $3 billion.One showstopper was a wall of five big, iconic “Woman” paintings from 1952-53, each of which could be worth $80 million to $100 million, auction-house specialists said. Hanging side- by-side, these violently painted figures resembled some prehistoric monster-goddesses.Another feat: a room full of rare “black” paintings from 1948-49, in which ghostly white lines intertwined on viscous black backgrounds.“Seeing it all at once is shocking,” said 16-year-old Lucy de Kooning, the artist’s platinum-blonde granddaughter, who grew up in a house on Long Island, where his studio remains intact (along with his paint-splattered shoes, motorized easels, buckets of brushes and scores of canvases).De Kooning moved to East Hampton in 1963 and lived there until his death in 1997 at 92.“He stayed Dutch as he became American,” said Elderfield, whose black attire was interrupted by the deep-green dots of his Issey Miyake tie. “That’s one of the reasons he moved to Long Island: to be near the water.”The curator helped identify body parts -- spread legs, an arm and even a stiletto -- in some of the pictures.“This is the heel, this is the toe,” Elderfield said, pointing at a group of black-and-white brushstrokes on the bottom of a 1977 painting. “He had this thing for high heels.”