''Time off to be an Oscar nominee/Now it's back to the M-I-C!'' Detractors might append that couplet with a ''...k-e-y M-o-u-s-e.'' But Smith's third post-Jazzy Jeff album, Born to Reign, is perfectly pleasant -- if somewhat jiggy-deficient -- Radio Disney-friendly rap. R&B; crooner Tra-Knox commandeers the choruses way too often, but Mrs. Smith displays surprisingly sweet pipes on the couple's agreeably self-involved duet, ''1,000 Kisses.''
