Despite decades of potential career minefields, Helen Hunt emerged as an Oscar and Emmy winner and one of the most popular actresses of the 1990s. She made the risky transition from precocious TV kid and mainstay in melodramatic movies-of-the-week to land a seven-year run on one of the era’s most awarded sitcoms, “Mad About You” (NBC, 1992-99). Then she made the nearly unheard-of turn from sitcom star to dramatic leading lady, with stellar performances in “Twister” (1996) and “As Good as It Gets” (1997). A grounded, intelligent professional who refused to take the “star” route and doggedly