Fats Waller, Handful of Keys. Every self-respecting record collection needs a generous slice of the collected works of Fats Waller, the stride pianist and comic singer whose 78s can put a smile on the sourest of faces. Proper Records’ imported four-CD box set, originally released in 2004 and readily available in this country, contains ninety-five tracks that come about as close as is possible to covering all the Waller-related bases. A few classics are absent, but if you don’t know what they are, you won’t miss them. Meanwhile, put on “Serenade for a Wealthy Widow” or “It’s a Sin to Tell a Lie” and see if you don’t become happier within seconds. No jazz musician–not even Satchmo himself–has ever succeeded in squeezing more joy into a three-minute package (TT).