This bubbly and attractive young actress so impressed viewers and producers of ABC's "Boy Meets World" that they made her recurring role a regular one in the 1994-1995 season. In her first appearance on the show in 1993, Fishel was originally to play a minor role, but was upgraded to Topanga, the girlfriend of Ben Savage's character Cory Matthews. On the show, the seriousness of the relationship between Topanga and Cory often belied their youth. Of the two, Topanga was the more free-spirited, and Fishel, with her striking features and girl-next-door appeal successfully portrayed a character