Fold preflop to the raise. AJo doesnt play well oop to a preflop raiser. Otherwise, fold the flop. How much money are you going to make if a diamond falls? Is your jack flush even going to be good?
I guess by the time I turn a big two pair, I'd have to decide based on what level of skill my opponents most likely have. If this is a 10$ tourney, for example, Id go with it. If it were a 100$ buy-in, I'd fold.