"What would you do if I died?"  Correct answer:  "Dearest love, in the event of your untimely demise, life would cease to have meaning for me and I would perforce hurl myself under the front tires of the first Domino's Pizza truck that came my way."

This might be the stupidest question of the lot, as is illustrated by the following stupid joke:

"Dear," said the wife.  "What would you do if I died?"
"Why, dear, I would be extremely upset," said the husband.  "Why do you ask  such a question?"
"Would you remarry?"  persevered the wife."No,  of couse not, dear" said the husband.
"Don't  you like being married?" said the wife.
"Of  course I do, dear" he said.
"Then why wouldn't you remarry?"
"All right," said the husband, "I'd remarry."
"You would?" said the wife, looking vaguely hurt.
"Yes" said the husband.
"Would you sleep with her in our bed?" said the wife after a long pause.
"Well yes, I suppose I would."  replied the husband.
"I see," said the wife indignantly. "And would you let her wear my old clothes?"
"I suppose, if she wanted to" said the husband.
"Really," said the wife icily.  "And would you take down the pictures of me and replace them with pictures of her?"
"Yes . . . I think that would be the correct thing to do."
"Is that so?"  said the wife, leaping to her feet.  "And I suppose you'd let her play with my golf clubs, too?"
"Of course not, dear," said the husband.  "She's left-handed."