GOOD MORNING: The first movie to be greenlit by Ron Meyer at Universal is “The Commandments,” to be produced by Ivan Reitman, who formerly was represented by CAA’s Michael Ovitz, who is wending his way to Disney on Monday. (Reitman’s agent at CAA now is Rob Scheidlinger.) “Commandments” quick-starts next month and is a low-budgeter –$6 million — to star Aidan Quinn and Courteney Cox. Daniel Taplitz directs his screenplay. This makes three pics in production by Reitman: “The Late Shift” for HBO, “Space Jam” for WB and now “The Commandments” at U. When will Reitman direct again? “When I find something with more substance, more weight.” (He has a big one ready to reel in — for U) … I found Reitman on WB’s Stage 22, the most unusual set where the Michael Jordan-Looney Tunes “Space Jam” is shooting. Jordan, in a basketball uniform of the Looney Tunes team, was doing a scene with “Seinfeld” semiregular Wayne Knight (Newman), also in the Tunes’ basketball uniform. The two were acting in front of an enormous greenscreen background that encircled the stage. The heat was almost unbearable in the Burbank studio as banks of lights prevented the actors from casting shadows. The actors included totally green-suited thesps from the Groundlings, who play the parts of the to-be-computerized and later inserted cartoon characters. Director Joe Pytka is no stranger to this kind of filmmaking — having directed the commercials with Jordan and the Looney Tunes characters for Nike. Pytka and Ed Jones of Cinesite told me this movie could not have been made a year ago — the Silicon Graphics technology has increased in such leaps, making it possible. “It’s so great,” Pytka said. “The actor has complete freedom , the cameras have more freedom.” Pytka revealed Bill Murray, who cameos, didn’t want to do the role, fearing lengthy technical setups. “Then he saw how easy it was,” Pykta said … The genial Jordan told me he loves being in his first feature and learning about filmmaking. Would he do other roles? He said he’d like to do movies like the James Coburn “Our Man Flint” features … Jordan is affable, photogenic, articulate — and a good actor, the company told me. But Thursday, they had to change the shooting sked in which he was to do a series of slamdunks — because he injured his right knee playing one-on-one with Reggie Miller of the Indiana Pacers on Wednesday night. Jordan assured me he’ll be OK by next week to shoot slamdunks for the pic. He departs today for the Chicago Bulls training camp preseason opener …”Space Jam” continues shooting until Oct. 23 and will be released Thanksgiving or Christmas — 1996.GORE VIDAL AND ROSEANNE — they were part of the New Yorker’s mix at L’Orangerie. The party was a toast to Vidal and his “Palimpsest” (Random House) memoirs, enthrallingly excerpted in the current New Yorker. Roseanne will soon ( 1996) be in the venerable, literate mag, as editor Tina Brown has Roseanne collaborating on “the Woman’s Issue,” While here, Brown and Roseanne brainstormed the issue, as did Carrie Fisher and Anna Deavere Smith. Brown apologized for not having published Vidal before, “although he just didn’t need the New Yorker to discover him!” He celebrates his 70th birthday Tuesday in N.Y. with longtime friends Joanne Woodward and Paul Newman — latter “is six months older than I,” smiled Vidal. He is ever-busy — writing the Alger Hiss story for Castle Rock, supervising the screenplay (by John Wilkman) of his “Screening History” for Hallmark, and — co-starring in “Shadow Conspiracy.” Others leading toasts to Vidal at L’Orangerie were Harold Evans, Random House president/publisher, and Bill Haber, Vidal’s CAAgent. The guest list ranged from Los Angeles D.A. Gil Garcetti to Barry Diller, from hallowed Hollywood’s Billy Wilder and Jean Howard to youngstars Courteney Cox and Christian Slater. “THE GOOD NEWS IS WE’RE NOT BLEEDING TO DEATH,” Jane Alexander, chairman of the National Endowment for the Arts, told me as the NEA celebrates its 30th anni today. “The voices of the Hollywood community and the artistic community around the country were heard,” she said, noting the 40% budget saving. On Thursday, the NEA presents its National Medals of the Arts at the White House with a dinner hosted by President and Hillary Clinton. Alexander will be in L.A. on Oct. 21 to give the keynote address at the Skirball Cultural Center bow … Actors for Actors holds a seminar Saturday at CBS Studio Center to train thesps to avoid scams, cons and ripoffs … Downtown Julie Brown, bowing as E! Entertainment Gossip Show host here Wednesday, was farewell-partied at N.Y.’s Mirage … David Hyde Pierce and Leeza Gibbons taped PSAs for Caring for Babies With AIDS’ Nov. 12 Stroll-a-Thon … Warren Beatty intros Mario Cuomo as the latter receives the Hollywood Women’s Political Committee’s Barbara Jordan Award , Oct. 5 at the Century Plaza. Mike Farrell receives the first HWPC Award for political and social activism.