As with bundy's parents, they're currently very, very good high school teachers. I think both of them would rather be teachers in a cultural and political environment that has more respect for the teaching profession.
Outside of that currently impossible wish, I'm sure my mother and father could have been a professional violinist and pianist respectively.
If they left teaching now, they might go and open a coffee shop. I think my father would enjoy getting a bunch of regular customers sitting around drinking espresso and playing scrabble while he dressed up in a tux like Rick from Casablance and played old George Gershwin and Noel Coward tunes on the piano.