There are, of course, two kinds - celebrity and civilian ones, depending on the competitors. The best celebrity one, beyond all peradventure, is 'I'm Sorry, I Haven't a Clue'. Good civilian ones were 'Ask the Family' and 'The Generation Game', and nowadays 'Countdown' is not bad. (BTW, it's Marina Hyde in the 'Grauniad' who calls non-celebs "civilians"). Worst? One I dimly remember from my adolescence in the mid-60s. I can't remember who presented it, what it was called, or whether it was celeb or civilian, but the idea was to guess which of three peoploe or things was genuine, for example - the only round I remember - three young women came on wearing trousers, and shuffling with their legs together. The teams had to guess which one had her trouser-legs sewn together so that she was obliged to walk like that. It was that pathetic. It didn't last long. Nowadays, 'Deal Or No Deal' is pretty crap, involving no skill or knowledge at all, and I hate the kind of quiz show in which the competitors are expected to chat abpout it instead of just saying what they think the answer is, e.g. the idiot who was asked which of four words was a medieval weapon. One word was "Mace", and he said "Well, I know mace is a deterrent spray, so it can't be that...".