Falstaff freshly observed. Shakespeare's `Henry IV' play in outdoor setting

Henry IV, Part I Play by William Shakespeare. Directed by Joseph Papp. Donald Moffat's superbly full-bodied Falstaff and a well-attuned ensemble provide a rewarding encounter with ``Henry IV, Part I,'' by William Shakespeare, at the Delacorte Theater. The New York Shakespeare Festival's 25th anniversary season of free Central Park performances is ending robustly.

With a delicately waddling gait and a paunch to match his mirth, Mr. Moffat's Falstaff creates a central, magnetic presence for the fluid action. A classically familiar figure is here freshly observed. When Prince Hal (Tony Soper) and Poins (Tony Shalhoub) face Falstaff with his cowardice during the Gadshill caper, Moffat pauses so long before delivering Falstaff's lame explanation that even a spectator familiar with the scene may wonder how the old rogue is going to get out of this one. But rascality, the mother of Falstaff's invention, doesn't fail him.

Later, in the cynical speech on honor, Moffat at one point delivers the word as scarcely more than an exhalation of breath. Such are the means by which this fine actor recreates a familiar figure in a portrait that touches some of the melancholy beneath the mirth. The approach contributes its own dimension to the play's recurrent contrasts between riffraffy high jinks and high-stakes power struggles. The impudent fun and games of the tavern mock interrogation end when the prince is called to court.

The two young Henrys - Prince Hal and Hotspur - are evenly matched in the performances of Mr. Soper and Conan McCarty. Soper delivers ``I know you all ...'' with only a hint of the Realpolitik which will bring the eventual banishment, not only of fat Jack Falstaff, but the other companions of the Boar's Head dissipations. The young actor even makes Hal's promise of reform, in the critical confrontation with Henry IV (an austere Michael Zaslow) moderately believable.

Mr. McCarty displays Hotspur's fustian without fully grasping the comic aspects of that fiery rebel. Perhaps it is just as well that Hotspur on this occasion is spared the verbal joust with Owen Glendower by the fact that director Joseph Papp has cut the scene in which Hotspur taunts the formidable Welshman.

It is one of the director's more successful fancies that this ``Henry IV'' is being acted at the Boar's Head Tavern, recently licensed for the giving of plays. Designer David Mitchell has provided an open stage against a period architectural fa,cade. Shakespeare designates the general setting merely as ``England.'' Mr. Papp and company achieve the illusion of changing locales by having the actors tote the spare, movable furnishings on and off stage as the needs demand.

The stage itself becomes a capacious platform for the scenes of action, notably the duel between Hal and Hotspur (excitingly staged by Malcolm Ranson) which leads to the conclusion of this episode in the cycle.

Papp has achieved a creditable sense of ensemble from his numerous cast. Alan Scarfe is a notable Worcester, the vengeful rebel who deliberately withholds from his nephew Hotspur the king's overtures of reconciliation, thus insuring the fateful encounter in which Prince Hal slays Hotspur. Among the more conspicuous members of the Delacorte company are Rocky Carroll (Sir Walter Blunt), Stephen Markle (doubling as Gadshill and Douglas), Tom Mardirosian (Bardolph), Chris McNally (Peto), Theresa Merritt (Mistress Quickly), Mr. Shalhoub (doubling as Poins and Sir Richard Vernon), and James Puig (Francis).

Theoni V. Aldredge's costumes add to the visual pleasures of this tumultuous revival and Jules Fisher's lighting ranges from shadowy murkiness for dark doings to daylight blaze for battle scenes. Composer Peter Golub's brassy flourishes and bagpipe skirls are equally stirring. (Through Sept. 13.)