Videocassettes : ****Excellent***Good**Fair*Poor : <i> Recent releases, reviewed by Times critics </i>

Dance

*** 1/2 “The Royal Ballet.” Bel Canto/Paramount. $29.95.

In this important 1959 performance film, Margot Fonteyn at 40 portrays three supernatural beings trapped by mortals. Besides dancing Odette in excerpts from Act II of the authentic Lev Ivanov “Swan Lake,” she appears in the title roles of Mikhail Fokine’s “Firebird” (in the 1926 restaging that Fokine repudiated) and Frederick Ashton’s three-act “Ondine”--both moderately abridged. Despite the disappointments of its faded, ruddy color and cramped frame-compositions, the film provides an invaluable touchstone of British classical style and an impressive index of Fonteyn’s artistry just before she began dancing with Rudolf Nureyev. (Her partner in each ballet here is Michael Somes.) The video release is remarkably timely, since “Ondine” is being revived this year in London for Gelsey Kirkland. Information: (213) 468-5000.