UPDATE, 5:30 AM Monday with a few more details: NBC celebrated the 40th anniversary of Jaws on Sunday night with a 3 1/2-hour tribute capped by Nick Ocean — surely the Hedwig of his day — singing “The Love Theme From Jaws” accompanied by Paul Shaffer on keyboard as behind them, clips ran of Bruce The Mechanical Shark munching on the good ship Orca and Captain Quint. It was hilarious. (See this and other clips in separate stories, below.)

In a calm, quivering sea of nostalgia desperate for a few shark alerts, Bill Murray’s raucous reprise of his Saturday Night Live lounge singer sparked some life into what was actually SNL 40, a celebration that ranged, predictably, from mawkish to absurd, shocking good (several newer cast members proved themselves deserving of a roost on the SNL Valhalla, a running joke that Jon Lovitz is dead) to shocking bad (when did Eddie Murphy morph into a sleek Beverly Hills avatar? When was the last time Chevy Chase saw his knees?) and even to a shocking instance of un-political correctness: a very funny compilation of SNL audition tapes featured Jim Carrey swiveling his hips while waving fake teeny arms as “Post-Nuclear Elvis.”

There was enough live funny business that, had Lorne Michaels and NBC kept the show to two hours, SNL 40 might have been brilliant. Instead, it was a long slog from dreary to plateau to intermittent high points provided by a guest list that seemed to stretch from here at Studio 8H in Rockefeller Center to eternity, with everyone apparently promised at least a cameo.

The Good Parts:

The Pauls. Near the top of the show, Simon and McCartney sang “I’ve Just Seen A Face,” with Simon grumbling as they left the stage, “I told you we should have done ‘Sound Of Silence.’ ” A little while later, Keith Richards introduced McCartney and band, performing “Maybe I’m Amazed.” Macca (who’d played an impromptu concert the night before at Irving Plaza for 1,000 happily stunned guests) was in good humor but terrible voice, as if it mattered.

Simon returned to close the show with — what else? — “Still Crazy After All These Years.” Before singing, he took the time to name every member of the band, including genius guest guitarist and former SNL (and Simon) bandleader G.E. Smith. Extremely classy.

“Weekend Update” There were clips of anchors of past and present along with a live segment that featured deskmates Tina Fey, Amy Poehler and Jane Curtin, along with guests invited to play their favorite SNL characters. That gave Emma Stone the chance to impersonate Gilda Radner as Roseanne Rosannadanna.

The Californians and Celebrity Jeopardy provided the chance for what seemed like scores of guests to make brief appearances in cherished recurring SNL sketches, and, like the originals, both wore out their welcome. But The Californians provided the chance to watch in horror as Bradley Cooper (blond!) played tonsil-hockey with Betty White (not blond!), while Celebrity Jeopardy gave us Will Ferrell in all his goofy glory as Alex Trebek (not to mention Kate McKinnon’s now iconic no-apparent-brain-activity Justin Bieber.

Jerry Seinfeld and Larry David dueting. Seinfeld came out onstage looking, um, patriarchal and immediately drew blood when he averred that he’d only just learned that Brian Williams was an original cast member of the show. He reviewed some old times with his former Seinfeld partner in the audience, who was, no surprise, grumpy in the end. Cut him some slack; his first Broadway show just began previews, and it’s being produced by Scott Rudin. No pressure!

Digital Short provided by Andy Samberg and Adam Sandler. After showing priceless clips of cast members and guests cracking up during sketches, their own new short was right up there with the best.

The Sad Parts:

Of course, there were tons of compilations featuring the Blues Brothers, Steve Martin, the original casts, cherished scenes from Samurai Delicatessen to the Bees. Long stretches of SNL 40 felt like being sentenced for the fourteenth time to watching Peter Paul & Mary or James Taylor’s fundraising concerts for PBS. Catnip to the Medicare crowd. It’s also sad that the show wasn’t big enough to mention sixth-season producer Jean Doumanian, whose shift introduced Murphy, Joe Piscopo, Denny Dillon and the late Charles Rocket. Not classy.

Fey and Alec Baldwin sent heartfelt greetings to former castmember Tracy Morgan, still recovering from a catastrophic car crash last summer. Murray introduced the inevitable necrology, and a hat tip to the show for including not just the obvious — Radner, Belushi, Phil Hartman, Jan Hooks, Chris Farley, etc. — but also the show’s deceased writers, backstage folks and others who kept the thing going for four decades. And Jon Lovitz.

The Bad Stuff:

Musical numbers: Miley Cyrus covered Simon’s “50 Ways To Leave Your Lover.” Why? Kanye West performed prone on the floor, facing the ceiling. Why?

The show opened with Jimmy Fallon and Justin Timberlake in a genre-crossing, mostly sorta-rapping musical tribute to the show as dopey as any awards ceremony opening number.

Chris Rock gave a dazzling introduction to Murphy, who came out looking like a dowager prince, had nothing funny to say, ended on an awkward pause and split. Huh? Seinfeld’s bit, about the overemphasis on number of times certain people have hosted the show, flatlined.

And then there were Martin Short and Maya Rudolph-nailing-it-as-Beyoncé, a sensational two minutes inexplicably killed, skinned and stretched to what felt like an hour before petering out altogether.

I’m not sure what it says that at several points it was impossible to know when the show broke and the ads began. Some were SNL parodies, but many were simply stupid ads that piled up — another reason for the unnecessary length of the broadcast — and left me with, as Tom Rush or Joni Mitchell would say, the urge for going. 11:30 PM came, and finally we were outta there.