"I didn't get to do half the things I wanted to do," Linda Lavin says at the end of her CBS special, "Linda in Wonderland," at 10 tonight on Channel 9. That may be just as well, since this is not exactly an hour that is chocablock with fun and frolic.

Lavin, who stars as "Alice" in the CBS sitcom, sings agreeably but no enthrallingly, and the material for the special is threadbare in that cloying star-turn way.

It was pure majic in 1954 when Ethel Merman and Mary Martin sat on stools and sang a medley on the Ford 50th anniversary show. But Lavin and guest Lynn Redgrave aren't really in the same league, to put it politely; their medley of parts-they-wish-they'd-played comes across as raggedy and harsh.

Anthony Newley, whose absence from the airwaves is always cause for elation, returns here still equipped with The Vibrato That Time Forgot. Someone has missed out on a great bit of casting, it becomes apparent, because when Newley slicks his hair back, he looks just like Richard Nixon. Or at least like Danny Aykroyd doing Richard Nixon.

He should play Richard Nixon. Then there would be no excuse for him to sing.

The musical low point is reached, however, with Lavin and her husband, Ron Leibman, a fine actor but not a snappy songster. Nor a snappy dresser, as he proves in an ugly cowboy shirt opened to reveal an unseemly hairy chest. As a couple, they bring to mind Fay Wray and King Kong.

There are highlights. Art Director Romain Johnston designed sets that usher in 1984 Chic four years early. Special effects enable Lavin to converse with Lavin as Alice, so deftly you can hardly tell how they did it. She's most attractive in the closing number when she gets off her high horse and spoofs herself.

Lavin may be one of those performers who are better off spoofing themselves than being themselves. There are many others -- but they can get their own specials. And they will.