Break the Bank for certain. A modern choice for me is The Rich List, and was glad to see GSN try to bring it back. Too bad it just didn't catch on here.
I'll go along with 
Break the Bank.  It make be a takeoff on 
Hollywood Squares, but I think it's a cleverly conceived and endlessly interesting show that didn't get a fair shot.
Fred Silverman cancelled it prematurely, despite strong ratings, because he was hell-bent on expanding soap operas.  Both 
One Life To Live and 
General Hospital were expanded from 30 to 45 minutes after the departure of 
Break the Bank.  I remember reading some time ago that it took the ratings a long time to climb back to what they were before the cancellation.
What they should have done was delay the premiere of 
Hot Seat - that was a waste of a half-hour - and move 
Break the Bank into that slot.  It probably would have had at least a few more months if that had occurred.