Speaking of hosts, I remember seeing Pinky Lee collapse on air while doing his frenetic dance routine. I suppose today they'd have "crisis counselors" or something for the kids ;-)
Betty Furness not being able to get the Fridigaire door open during a live commercial sticks in my mind, too. I can still hear my parents' howls of laughter.
That was similar to when a rotating stage got stuck between scenes on the Jackie Gleason show. The show was live, and Jackie had to come out in front of the curtain and riff, puffing cigarettes and sweating, for a long, long time.