The comic and soon-to-be-talk-show-host Howie Mandel is reclining in his office on the NBC lot, looking at videotape of variety acts. He lingers on the cast of "Tap Dogs" and the juggling Flying Karamazov Brothers, but fast-forwards past a young violinist.

What's the matter, too high-brow for a talk show?Mandel admits as much, but then throws a curve ball: "Did you know my cousin is Itzhak Perlman?"

In the pregnant pause that follows, you're not sure whether he's serious or joking. That's an apt feeling to have, because as Mandel heads toward the Monday debut of his daily syndicated "Howie Mandel Show," you're not quite sure whether he's going to do it straight or as a ham.

"There's a contingent of people who'll expect me to be silly," says the comedian whose bread-and-butter bit used to have him inflating a latex glove on his head.

But Mandel points out that he's long since moved away from his inner prop comic; his last HBO standup special, "Howie Mandel on Ice," had him getting into more serious topics like marriage and parenthood.

Meanwhile, Mandel's talk-show persona, like his show, is still a bit of a work-in-progress. At the time of this interview, three weeks before going on the air, the show had just dropped Brianne Leary, Mandel's announcer and sidekick, after test shows indicated to the producers that Mandel was better off kibitzing with the audience than with a paid professional standing in the wings.

In the end, however, the only thing about "The Howie Mandel Show" that really matters is Howie Mandel. Like other new arrivals to the talk show game (Magic Johnson, Donny and Marie Osmond, Roseanne), Mandel will last only as long as his charm and appeal do.

"At the end of the day," says Frank Kelly, co-president of domestic television at Paramount, the studio backing the show, "after the sets and the staff and the band and the bookings, that's what's going to matter."

Mandel couldn't agree more.

"What makes any show work is the personality behind the desk," he says. "The success of `Rosie O'Donnell' is because of Rosie, the success of `Oprah Winfrey' is because of Oprah."

Giving a visitor a guided tour of his new digs in Studio 1, Mandel comes to rest in the bleachers where the studio audience sits. It's roughly the same spot he occupied in the 1970s when, as a fan, he came to see the room's former tenant, Johnny Carson, run "The Tonight Show." At the time, Mandel was recently relocated to Los Angeles from Toronto, having given up the carpet business for standup comedy.

He would cut his teeth at the Comedy Store as an energetic comic whose goofiness gave audiences the sense that he'd do just about anything.

These days he's the more refined, less antic Mandel. The hair is flecked with gray, making him look almost distinguished; the clothes are closer to an agent's than a clown's. Mandel, you get the feeling, is slowly morphing into a smooth talk-show creature, making the same transition that his next-door neighbor at NBC, Jay Leno, has made.

But while Leno entered the talk-show field and locked horns with David Letterman in a battle for late-night supremacy, Mandel's competition is different.

He's entering a daytime field dominated by women, from nurturing authority figures (Rosie, Oprah) to in-your-face bad cops (Sally Jessy Raphael, Judge Judy).

"I don't have to be No. 1," Mandel says. "I don't have to win an Emmy. My biggest worry is not being able to do this as long as I want to."

Mandel didn't go digging for this opportunity. He filled in several times for Regis Philbin on "Regis & Kathie Lee" and impressed enough people with his relaxed manner to get multiple offers for his own show.

He balked at first. "I thought doing a talk show every day would be boring," he says.

But then he did the math: He could continue doing an average of 200 dates a year on the road with his standup comedy, or he could try his luck at a talk show, which, if everything goes right, will keep him in L.A. with his wife of 20 years and his three children.

"I haven't been spending enough time at home, and now I'm home every night," he says.

Mandel, 42, has taken creative detours in his career before. In the 1980s he proved he could do prime-time drama when he took on the role of Dr. Wayne Fiscus on NBC's long-running "St. Elsewhere."

The 1990s turned him into a cartoon - literally - when Mandel developed the high-pitched kid's voice he did onstage into "Bobby's World," a cartoon still running on Fox.

Still, Mandel will likely be most readily identified as a standup comedian.

In fact, it's those tireless years on the road that helped draw Paramount's interest.

"When you have someone who has that appeal in Middle America and college towns and big cities, that's a good sign," Kelly says.

For now, the fledgling talk-show host is taking delight in the newness of it all.

"I've got a lobby and a theme song," Mandel says, with kidlike awe. "What more do I need?"

Oh, and by the way, he really is related to Perlman. They're distant cousins on his mother's side.

Beginning Monday, "The Howie Mandel Show" will be seen weekdays at 3 p.m. on Ch. 2.