George Burns, Gene Kelly, Whoopi Goldberg and Joan Collins are among a number of celebrities participating in "A Vision of Home," a unique auction to benefit homeless families. Each celebrity will receive a Polaroid Spectra camera and film. Their "assignment," said Linda Ford, chairman of the Spare Change Project, "is to capture their individual impressions of home - a favorite room, street, garden or anything that evokes the natural, essential comfort or personality of a place that means `home."' A panel of photography experts will judge the photos and select each celebrity's most outstanding compositions for auction. The photos will be enlarged, signed, framed and auctioned off at a gala reception Jan. 31. Proceeds from the auction will go toward providing funds for the Family Assistance Program to aid homeless families in finding housing, employment, job training, educational opportunities, child care and financial assistance.