The Albright-Knox is the best art museum in the Buffalo area. It's moderately sized with an area that's open to the public. There is also an exhibition area that changes exhibitis regularly. Collections from other art galleries, personal collections, etc. will come here and make their stay for several months. These are usually very nice exhibits and have included Modigliani, Renoir, da Vinci, in the past.
During the summer, the Albright-Knox has a free jazz series in it's backyard. This is a great place for all to come and sit out and enjoy.