Audiences desperately need a laugh right now, and the fall theater season is riding to the rescue with farces, rom-coms, political satires and musicals with a sharp sense of humor. One farce should come with a surgeon general’s warning. Richard Bean’s “One Man, Two Guvnors” had me in physical distress when I saw it first at London’s National Theatre and then again on Broadway. I nearly asphyxiated from laughing. Whether A Noise Within will be able to capture the slapstick panache of James Corden’s Tony-winning performance in “One Man, Two Guvnors,” is an open question. But the mere memory of this reworking of a commedia-style classic leaves me in stitches. “Eureka Day” is no less amusing for being politically pointed. Jonathan Spector’s play, set at a super-woke private school in Berkeley, wades into the ever-more contentious vaccine debate. How can concerned parents reach consensus when even medical knowledge has become tribalized? Spector satirizes with just the right combination of empathy and mercilessness. Hard to think of a finer recent workplace comedy than “Jaja’s African Hair …