SUPER MARIO WORLD 2: YOSHI'S ISLAND

SUPER MARIO WORLD 2: YOSHI'S ISLAND (Nintendo, for Super NES, $69.95) It's been four years since the original Super Mario World for the Super NES, and in that time Nintendo appears to have learned a valuable lesson: that it had better put its microchips in gear before it gets eaten alive by Sony and Sega. Accordingly, Yoshi's Island is the best Mario adventure yet, a deep, rich, challenging prequel in which a herd of Yoshis (cute little dinosaurs) have to keep a squalling baby Mario out of harm's way. And the look of this game is amazing -- the stages, with their pastel backgrounds and goofy monsters, are like pages from an award-winning children's book. A