I've put in way too much thought into this. I can already tell you that at some point in this, I will contridict myself.
I believe stupid people are happier. They do not have to deal with not being able to explain their thoughts to "normal" people or the immense amount of work I put myself under in order to obtain a more sophisticated outlook on the world. They do not have to deal with the stresses that come with being smart.
Here comes the contridictions. Just some thoughts that I had come up with while despretly trying to deal with life. Although stupid people do not have to deal with the same issues that smart people have to deal with, I believe that they also have issues. To the intelligent population, they seems trivial, but to them, the probably seem as big as the end of the world. They are not as smart and therefore do not know how to deal. Intelligent people have the added struggle of working with "normal" people, but stupid people have the same problem, but as not seeming stupid to "normal" people.
I do not in any way regret being smart. I like it, but at times it can seriously be a burden, and it is then that I want to stupid. I think that the best place to be at, intelligence speaking, is in the middle, because then the majority of the population is like you and there is that many more people who will understand and be like you. Anyways, that is my thought on the matter.