Cooking breaks down the hard cell walls of plants to some degree making nutrients more available and reducing toxins such as those that harm your thyroid in cruciferous vegetables. With all the recalls of produce going on now and then I think it's safer to cook them to kill bacteria too.
I still eat raw fruit and some vegetables raw but I wash them very, very well.
Overall I think cooking is the way to go until I stop seeing so many recalls of contaminated produce.
I even got concerned enough to heat up melon a little in the microwave before eating a couple of times because of all the people getting sick from eating tainted melons.