Although she left General Hospital in 1981, Brooke Bundy still gets recognized from her four-year stint as Diana Taylor, nice nurse, single mother, and eventual murder victim. It's clear some GH faithful just can't believe she's moved on. ''Just the other day,'' Bundy relates, ''this woman said, 'Oh my God! You're Diana, from my show.' '' Five years ago, Bundy gave up acting to become an agent for child stars, handling Madeline Zima (The Nanny) and Will Friedle (Boy Meets World), among others. She no longer frets about job security: On GH, she says, ''I was always alarmed. One time, I saw in the script I had a brain tumor. When I asked [then executive producer] Gloria Monty if I was being fired, she said, 'Why? It's just a brain tumor.' I said, 'Well, those are usually fatal.' 'Oh honey,' she said. 'Never on a soap. Get real.' ''