"The Best of Broadway" was the National Symphony's program last night--and a well-titled program it was. While some might have quibbled over a few selections, Broadway has never had better than Cole Porter, George Gershwin, Leonard Bernstein and Stephen Sondheim.

All have enjoyed wild commercial success without sacrificing art or falling into a rut. And all are American composers of the first rank.

Before a full house in the Kennedy Center's Concert Hall--still festooned with holiday bunting--associate conductor Hugh Wolff led the orchestra and three singers through such timeless tunes as Porter's "I Get a Kick Out of You" from "Anything Goes" (1934), Gershwin's "I Got Rhythm" from "Girl Crazy" (1930) and Bernstein's "Times Square" from "On the Town" (1944).

There were also medlies from Sondheim's macabre hit "Sweeney Todd" (1979) and from that irresistible finger-snapper--sporting Bernstein's music and Sondheim's lyrics--"West Side Story" (1957).

It was, on the whole, a pleasant enough evening, despite a tinny sound system that did the singers no great service, moments when the orchestra was out of balance and occasional overeager baton-wielding by Wolff. In the program opener, Bernstein's Overture to "Candide," the conductor looked and sounded like a young man in a hurry.

When these numbers were done on Broadway, the musicians were in a pit under the stage. Last night the singers shared the stage with a full-sized symphony orchestra. Most of the time it didn't work.

The singers, all local, were soprano Dorothy Kingston, her husband, baritone David Troup, and tenor Stanley Cornett. While they managed to convey infectious good cheer, they didn't often convey the lyrics. Except in the "West Side Story" medley, for which the orchestra was pared down and sotto voce, they were variously overwhelmed and undermiked.

Cornett, with his even, controlled tenor and clear diction, was the most successful--in "Maria," and with Troup, in the "Jet Song" from "West Side Story." Kingston was fine in "I Feel Pretty"--with the men sassily singing what Bernstein wrote as female counterpoint--but seemed to have trouble elsewhere.

Her rendition of "I Get a Kick Out of You," against an over-lush accompaniment, sounded about as kicky as an old shoe. In the "Sweeney Todd" medley, meanwhile, Sondheim's syncopated rhythms and cunning orchestrations sounded a bit like a traffic jam. This is difficult music, as the orchestra knows. The program, with radio personality Tom Gauger serving as host, will be repeated tonight.