People, in general, choose peace; to put it in words more people would agree with, people choose peace if they're directly accountable for and affected by going to war. Democratic societies, even if the democracy is not direct, will always be more peaceful because the leadership cannot decide to go to war on a whim.
Yes, I believe the democratic peace theory is correct. This is because, firstly, I believe democratic leaders should have to accept culpability for negative consequences brought about by war losses to a voting public. Also, the democratic peace theory causes democracies to be less likely to view countries with dissimilar policies as hostile.