JUST AS the KB chain decided to combat the pre-summer blahs with a Broadway musical series at the KB Cinema, the Circle has set aside its Dupont Circle house for a 25-film Alfred Hitchcock festival, beginning this Friday. The roster: North by Northwest and To Catch a Thief (Friday and Saturday); The 39 Steps and The Lady Vanishes (Sunday and Monday); The Wrong Man and Shadow of a Doubt (Tuesday and Wednesday); the series' only triple bill, Secret Agent, Sabotage and Murder (Thursday only); Rear Window and the 1956 remake of The Man Who Knew Too Much (May 24 and 25); Vertigo and Spellbound (May 26 and 27); Dial M For Murder and Strangers on a Train (May 28 and 29); the 1935 version of The Man Who KnewToo Much and Young and Innocent (May 30 only); Rebecca and Notorious (May 31 and June 1); Blackmail and The Birds (June 2 and 3); Rope and The Trouble With Harry (June 4 and 5); and Psycho and Number Seventeen (June 6).

The National Archives has resumed its free weekly film program with an ambitious examination of The War Film. Scheduled to last until December, the program will present a collection of documentary and fiction films. Daytime screenings will feature war footage from the holdings of the Motion Picture, Sound, and Video Branch of the National Archives (the largest non-fiction film collection in the world), while evening screenings will focus on the dramatic treatment of war from the silent era to the end of World War II.

This Friday at noon, Frank Capra's rarely seen 1945 documentary Here Is Germany will be shown. Produced by Capra and Anatole Litvak from a script by Anthony Veiller, Ernst Lubitsch, William L. Shirer and Gottfried Reinhardt (who directed the 52-minute film), the film traces Germany's military development via voice-over narration by Veiller and Walter Huston. The next fiction film in the program is King Vidor's silent World War I drama, The Big Parade, screening Thursday at 7. Pianist Robert Vigoda will provide live musical accompaniment.

Other coming films include an encore of the documentary Raoul Wallenberg: Buried Alive (May 24 at noon); Thunderbolt, a 1945 documentary on the 57th Fighter Group in action over Italy during the Allied "Operation Strangle" campaign (May 31 at noon); and Alfred Hitchcock's Foreign Correspondent (June 6 at 7). The Archives screening facility is on the fifth floor, easily accessible through the Pennsylvania Avenue entrance. The schedule through June 28 is available by calling 523- 3347; the July-through-December programs will be issued before each month's screenings.

'Tis the season for benefit premieres of summer films:

*Friday night at 8, the Embassy Circle theater is the site of a screening of Rambo: First Blood Part II to benefit the National Vietnam Veterans Network. There's a $10 minimum donation at the door; for information, call 833-4156. "Rambo" is now set to open nationwide on Wednesday.

* The Richard Pryor vehicle Bewster's Millions will have its world premiere on Tuesday at 7. The Tenley Circle screening will be followed by a reception; the event will benefit the Black American Response to the African Crisis (BARAC), a coalition organizing a nationwide effort to assist victims of famine. Tickets are $100 per person; for reservations, call 726-3204. "Brewster's Millions" opens Wednesday.

* Walt Disney's Fantasia will screen at the newly remodeled Circle Avalon on Wednesday at 7:30. The event is hosted by Woodward & Lothrop, with proceeds supporting the National Symphony Orchestra. Tickets are $10. The show is the East Coast premiere of "Fantasia" recorded and presented in full digital stereo. While this is essentially the same digital audio rerecording of Leopold Stokowski's score that the film was rereleased with in 1982, a recent technical breakthrough at Disney means movie theaters can now use a playback system capable of true digital stereo. The refurbished Avalon boasts a slightly curved, 850-square-foot screen and the latest in 70mm technology. For further information, call the Circle offices at 331-7471. "Fantasia" will have a two-week run at the Avalon beginning May 24, and move to conventional stereo engagements June 7.

A reminder about the Showcase of Eastern European Cinema to be mounted by the Smithsonian Resident Associates Program. Starting Tuesday, two rarely seen and/or new films from participating countries (The German Democratic Republic, Romania, Poland, Bulgaria, Hungary, Czechoslovakia and the Soviet Union) will be show on consecutive Tuesdays at 8 in the American History Building's Carmichael Auditorium. Tickets are $40 for members and $46 for non-members, with individual screenings priced at $6 and $7.50.

Also on tap from the Resident Associates is a free natural history film/lecture series, running for the next three Fridays at noon. This Friday, an hour-long documentary called 18 Corridors of Time will give a history of the Colorado River region (this and the remaining two films are part of the 1983 BBC series "The Making of a Continent," and all run an hour). The Land of the Sleeping Mountains (about the formation of the Sierra Nevadas) will be shown on May 24; The Price of Gold, an exploration of the Sierra Nevadas and the 1849 gold rush, screens on May 31. All screenings will be in the Baird Auditorium of the Natural History Building. For information, call 357-3080.

Northern Virginia residents have four more screens as of this Friday, as the Tackett's Mill Cinema IV opens in Lake Ridge, about an hour south of D.C. The complex is operated by Showcase Theaters, which is the suburban branch of the Circle organization.

PAGES OF FILM HISTORY -- Happy birthday this date to actress Maureen O'Sullivan (Mia Farrow's mother), Dennis Hopper, singer Taj Mahal and Sugar Ray Leonard. It was on this date 61 years ago that Metro Pictures, Goldwyn Pictures, and the Louis B. Mayer Company joined forces to become Metro Goldwyn Mayer (MGM). In 1973, live television coverage of the Watergate hearings began.

Saturday's birthday people include director Frank Capra, Perry Como, Pope John Paul II, Pernell Roberts and baseball greats Brooks Robinson and Reggie Jackson. Mt. St. Helens erupted five years ago Saturday, and it was on that date in 1969 that the first live color TV pictures were beamed down from space, courtesy of Apollo 10.

Eddie Cockrell is a freelance film consultant and teacher. His "Insights on Film" is heard Mondays at 5:30 p.m. on WGMS AM & FM.