Mahler’s Fourth Symphony is perfect for this haunting time of year, when Standard Time plunges the days into darkness and we celebrate Halloween and the feasts of All Saints and All Souls. With its message of light triumphing over darkness, it is the brightest and the most popular of Mahler’s symphonies. The luminous first movement begins with sleigh bells. But in the scherzo, Mahler delves into his dark side, evoking a spooky figure of German folk legend who leads a dance of death. In the last movement, he returns to the religious themes that radiate through so much of his music, with a soprano singing a childlike song about the joys that await the saints in heaven. Soprano Mary Wilson sings that beautiful song this weekend, when the Buffalo Philharmonic Orchestra, led by JoAnn Falletta, performs the symphony at Kleinhans Music Hall. The concert is the first of a glittering handful of concerts that take audiences back in time to pre-World War I Vienna. Opening the program is one of the loveliest musical creations of the 20th century, Arnold Schoenberg’s tone poem “Transfigured Night.” Catch the concert at 8 p. m. Saturday and 2:30 p. m. Sunday. Admission is $25 to $57. For more information, call 885-5000. —Mary Kunz Goldman