The opera that opened brilliantly Saturday night in the Eisenhower Theater raises some of the most sensitive issues of our time: terrorism, relations between Europe and the Third World, and women's rights, to name only three. It suggests no satisfactory solutions to any current problems, partly because it is a very frothy comedy and mostly because it is nearly 175 years old. But for anyone who wants a few good laughs and an evening of lilting melody, this production of Rossini's "L'Italiana in Algeri" is well worth seeing.

"L'Italiana in Algeri" ("The Italian Woman in Algiers") dates from 1813, a time when the Barbary Pirates were still earning a substantial part of their GNP by kidnaping Europeans and either selling them into slavery or holding them for ransom. This industry, finally stamped out when the French conquered Algiers in 1830, may not seem a promising theme for a comedy, but it was a well-worn subject (in Mozart's "Abduction From the Seraglio," for example), long before Rossini's time. Angelo Anelli's libretto rises above routine in two ways: by inspiring some of Rossini's most sparkling music and by creating a striking and memorable heroine, Isabella, to serve as an enlightened European contrast to the subjugation of women in Islamic society. In the right hands (and the Washington Opera has certainly put it into the right hands) it also has moments of slapstick comedy that can make your ribs ache.

Originally presented here in the 1984-85 season, "L'Italiana" is the first Washington Opera production to be moved from the Terrace Theater to the company's new downstairs performing space in the Eisenhower. The transition is, on the whole, a successful one. The company has kept the outstanding strengths from the production's first time around -- the performances of mezzo-soprano Mimi Lerner and basso buffo Franc ois Loup -- and has added to them outstanding work by bass Jan Opalach, soprano Pamela South and others. Zack Brown's scenery, made up mostly of pillars, panels, pillows, a lifeboat and an antique Mercedes-Benz, adapts easily to its new environment. The acoustics and sightlines are excellent and the atmosphere is almost as intimate as it was in the Terrace.

For most of the audience, the chief difference from the last time this production was shown will probably register as a net gain: The Eisenhower allows surtitles, which were not technically feasible in the Terrace. As usually happens when surtitles come in, the audience is now laughing at verbal sallies that were previously met with silence.

As it happens, the surtitles for "L'Italiana," while they match the quality found in most American opera houses, are not up to the best standards set by the Washington Opera in the past. The translations occasionally rhyme but seldom try to match the rhythms of the words being sung; the mots are not always as juste as they might be, and there are long stretches of singing unmatched by any words on the overhead screen. Still, a comedy with sketchy titles has perceptibly more impact than a comedy with no titles at all, and this "Italiana" has undoubtedly acquired clarity with this addition.

Still, the heart of the opera now, as it was three seasons ago, is the confrontation between Lerner and Loup. Loup plays Mustafa, Bey of Algiers -- a Third World potentate slightly dotty about European culture and most particularly about the spirited young women of Italy. "You must find me an Italian woman," he tells Haly, chief of his palace guards and a free-lance pirate, well played by baritone Gordon Hawkins. "I have a great desire to possess one of those young ladies who torment {literally, who give the hammer to} so many suitors."

Lerner is Isabella, the hammer-wielder of his dreams: a young lady from Italy who is considerably smarter than any of the men in the show. In the first scene, the theme may be "Mustafa, tamer of women," but by the last scene one feels that somebody should start a "Save the Bey" movement. Portrayal of Isabella requires a performer of formidable stage presence and self-possession as well as a virtuoso voice with a wide range of pitch and dynamics and finely controlled coloratura. Lerner has all these resources and knows exactly how to use them. She is perfectly matched to the role, and it is a delight to see her in action.

Loup is, as always, a master of timing and outrageously exaggerated gestures. His control of comic facial expressions has almost as much impact in the Eisenhower as it did in the Terrace, and whether he is climbing a ladder to eavesdrop on Lerner, rearranging pillows for purposes of seduction or getting a lesson in how to eat spaghetti, he has the audience laughing so hard that they may not notice how well he sings.

This oversight can be remedied next Monday, when he will make his Western Hemisphere recital debut in the Eisenhower, which will also be making its debut as a venue for such a program. Loup's talents as an operatic comedian have become well known from San Diego to Washington, but in Europe he is still best known as a recital singer specializing in baroque and contemporary repertoire. His recital program will include Mussorgsky's powerful "Songs and Dances of Death" as well as drinking songs and "off-color songs." This concert may be a revelation to many of his fans, but not to those who have listened carefully to his singing in "La Cenerentola," "L'Elisir d'Amore," "Don Pasquale" and other productions of the Washington Opera.

Definitely a revelation on Saturday night was the highly polished comic skill of Jan Opalach, a bass who has sung often in Washington but usually in the music of Handel and never before in a staged opera. His portrayal of the aging gigolo Taddeo revealed dimensions in Opalach's talent that could not be deduced from the way he sings "Behold, I tell you a mystery." He will sing later this season in the Washington Opera's "Cendrillon," and his return will be eagerly awaited.

Pamela South and Gloria Parker have already made favorable impressions on Washington audiences, South in "Don Pasquale" last season and Parker in "Romeo and Juliet" earlier this season. They both reinforced those impressions with expert performances. Tenor Marcus Haddock, who performed well as Tybalt in "Romeo," took an uncomfortable while to warm up on opening night but sang well in Act 2.

Gordon Hawkins, who is gradually solidifying his presence in comprimario roles with the Washington Opera, showed substantial advances as an actor in his portrayal of Haly, and his big aria, "Le femmine d'Italia," was sung with the polish one expects of a seasoned performer in a major company.

The male chorus performed with vitality and a fine sense of theatrical values -- undoubtedly reflecting the work of stage director Leon Major, whose staging was deft and effective. The updating of the story to this century involved some amusing anachronisms but also gave the show a piquant and distinctive style. Conductor Joseph Rescigno matched the show's visual impact with properly crisp and excellently balanced music.