I know a lot about them, except I have no idea what their "one hit" would be. "One Week"? "If I Had A Million Dollars"? "Be My Yoko Ono"? "Brian Wilson"?
I have their first five studio albums, as well as Rock Spectacle, a live album. I like them all, but unfortunately I don't think they've ever come close to the brilliance of Gordon, their debut album. That is probably a desert island selection for me. I have seen them live several times, all while Stephen Page was still in the band, and they were great every time. And hilarious.