I'd rather be a happy idiot than a depressed scholar.
Oh, I'm still aware of all the bad and the wrong that happens in the world, I just try not to think about it if I can help it; I'm a very emotionally-based person and I get depressed real easy-like. And let it be known, your poll is a little strange. It ranges from "dumber than a bag of bags" to "knowing everything that was, is, and ever will be" with only three spots of middle ground. That said, option 3 probably suits me best. Although, if I could have it my way, I'd have a cross between 2 and 3. Something like "ignorant of human suffering, but still well-read."
Although, if I was completely unaware of human suffering, I probably wouldn't be the (self-proclaimed) nice guy I try to be all the time.