Sade was the silken sound of R&B in the ’80s, smooth enough to fit all manner of nascent “adult contemporary” formats, yet her sensuous sophistication helped her transcend radio marketing categories. The British singer’s lustrous singles are collected on this two-disc set, with pride of place going to the evocative pop of “Smooth Operator” and the urbane funk of “The Sweetest Taboo.” The set concludes with a bid for younger listeners in the form of remixes involving Jay-Z and The Neptunes.