I'd rather know than be happy. I want to know everything. In knowing everything I can make the best of it. If the knowledge makes me unhappy for a longer time than I wouldn't be able to differentiate (sp?) between happiness and unhappiness.

One of my favorite quotes "Endure. In enduring, grow strong.", this essentially means that if faced with knowledge that makes one unhappy just endure and come out a better man. And who doesn't want to improve oneself?

And to answer Ilyas question why atheist rather wants know than be happy, the same reason as you stated. Curiosity.

By the way, are you an atheist or theist Ilya?