"Odi et Amo," a lecture and multi-media concert on the poetry of Catullus, will be performed by the DeReggi InterArt Ensemble Saturday and Sunday at 7:30 at the French Embassy, 4101 Reservoir Road NW, as part of the Cross Currents Festival; $10, $8 for students and seniors; 428-3174 . . . There'll be a lecture/concert of Yiddish songs Sunday from 2 to 3:30, featuring soprano Cantor Margaret Brenner and tenor/accordionist Michael Feldman at the Small Jewish Museum, 701 Third Street NW. The program complements the museum's exhibit "We Came Through Ellis Island"; $3, $4 for non-members; 881-0100 . . . The Washington Music Ensemble presents a free program of romantic French vocal music, part of its Festival France '85, Sunday at 7 at the National Gallery of Art, West Garden Court, West Building; 587- 7976. IN VIRGINIA The Northern Virginia Handcrafters Guild holds its annual craft show at Tysons Corner Center Friday from 10 to 9:30. More than 100 guild members will participate and craft demonstrations will be given through the day; free admission; 280-5015 . . . There'll be a free reenactment of George Washington's last review of his troops Saturday at 11 a.m. on the steps of Gadsby's Tavern Restaurant, 138 N. Royal Street in Alexandria; 549-0205.