NEW YORK - On his final "Tonight" show, Conan O'Brien said walking away instead of accepting a demotion is the hardest thing he's ever had to do.

Despite the rancor that led to his $45 million buyout, the red-haired comic urged fans not to be cynical and said their support made a sad situation "joyous and inspirational." He thanked his viewers and even thanked NBC for more than 20 years of employment but not before getting in a few final jabs during an earlier monologue.

O'Brien will be replaced March 1 by the man he took over for seven months ago -- Jay Leno. In the interim, reruns will fill the slot, followed by Winter Olympics programming next month.

Faced with the flop of its prime-time Leno experiment, NBC sought to move him back to 11:35 p.m. and asked O'Brien to move "Tonight" a half-hour later, past midnight. O'Brien refused, opening buyout negotiations that ended early Thursday, and triggering a remarkable period of late-night comics taking brutal shots at NBC and at each other.

Despite his sense of loss, O'Brien told fans Friday that "I really feel this should be a happy moment.

"Every comedian dreams of hosting the `Tonight' show and, for seven months, I got to," he said. "I did it my way, with people I love, and I do not regret a second. I've had more good fortune than anyone I know, and if our next gig is doing a show in a 7-Eleven parking lot, we'll find a way to make it fun."

Tom Hanks, Will Ferrell and Neil Young joined O'Brien for his final show.

His future is uncertain. Fox has expressed interest in having him do a late-night show, but the network is checking with its affiliates to see if they would support it. Under his exit deal, O'Brien is free to start another show after Sept. 1. He's not allowed to give interviews or make other television appearances for three months.

During his monologue, O'Brien tossed around a few ideas about what NBC might do with the studio it constructed for him when he moved to California from New York in the middle of last year.

One suggestion: "Leave the studio cold and empty and rename it `the world's largest metaphor for NBC programming.'"