Hold on to your love beads, Baby Boomers. Ringo Starr has become Captain Kangaroo! Sort of.

Starr, the rock drummer who rode the Beatles express to the farthest reaches of pop culture stardom, will be making his debut as a children's TV show star Jan. 28 when PBS's "Shining Time Station" premieres. In the half-hour series, Starr plays a magical 18-inch-tall railroad conductor who loves to tell railroad stories to children.That's quite a leap from the impish rock star we all remember, isn't it? Or is it?

"I look at things as they come up," Starr told reporters meeting here at the Registry Hotel for the annual winter network press tour. "My life has always been sporadic. I've been playing on a couple of sessions with some of my friends. I've done some movies. I've done some TV. I just do whatever comes up that interests me.

"But because I'm doing this doesn't mean I'm not going to drum anymore. I'm not planning on spending the rest of my life playing 18-inch-tall train men."

Indeed, the bearded grandfather (yes, Ringo's a grandfather, complete with streaks of gray in his thin, shoulder-length hair) has a hard time seeing himself playing anything at all for an extended period of time.

"I don't count myself an actor," Starr said. "I'm a personality who says the lines they tell me to say."

"Shining Time Station" is a weekly series produced by New York's WNET, aimed at pre-school children and their families. The idea for the show was born soon after producers Britt Allcroft and Rick Siggelkow saw an English TV series in which Starr narrated the animated stories of Thomas the Tank Engine.

"It was a natural progression for me to move from narrating those stories to this half-hour series," Starr said. "And it's a great chance to work with children. I enjoy working with children, I really do. I used to be one, you know."

It's an old joke, but it logically leads to a new question: How do the children in the cast like working with a living rock music legend? "I had heard of the Beatles," said Starr's 8-year-old co-star Jason Woliner, "but I hadn't really heard about Ringo. But now I love to listen to Beatles songs and hear him drumming."

"I've heard of a lot of famous groups, but not the Beatles," 8-year-old Nicole Leach admitted. "Were they as popular as the Jets?"

Didi Conn, an experienced actress ("Benson," "Grease" and "You Light Up My Life") who has appeared in Utah with the Salt Lake Acting Company, didn't need to be reminded of who her new co-star was.

"I never made it inside a Beatles concert, but my girlfriend and I once stood outside where a concert was being held and screamed a lot," she said. Then she added: "Ringo was our favorite Beatle."

So when she finally met Starr for their first rehearsal together, she tried to play it really cool. "I kept telling myself, `He's just another colleague - it's no big deal,' " Conn said.

"Then after the rehearsal was over I went into my dressing room and screamed."

Her girlfriend would have been proud.

There aren't a lot of teenaged girls screaming for him these days. "The 1960s were very fast," he remembers. "Things have settled down a lot since then." Still, he likes his lifestyle ("Rich and famous," he quipped) and the way he has been able to live his life.

"Things have turned out fabulous for me," he said, sounding every bit as cheerful and optimistic as he looked.

And maybe even as cheerful and optimistic as - dare I say it? - Captain Kangagroo.

- AN ERA WILL END this spring when Vincent Price makes his last appearance as the host of PBS's "Mystery!" anthology series. Price, who has been hosting the series since January 1981, asked to be replaced as host "in order to pursue other interests," he said.

"Vincent Price brought to `Mystery!' a lifetime of devoted fans and an appeal uniquely his own," said series producer Rebecca Eaton.

"He's led our viewers through a maze of thickening plots, suspects and murders and helped make `Mystery!' a viewing addiction for thousands of people. His enthusiasm and courtliness have never faltered. We will all miss him."

Indeed we will.