Generally speaking the big draft breeds like Belgians and Clydesdales tend to be calmer horses. Hot bloods like Arabians, Saddlebreds and Thoroughbreds amongst others, are very smart and spirited breeds.
Every breed and individual horse is different. You can never be sure what your horse's attitude with turn out to be like. But some times you can estimate a breeds general behavior. Arabians can tend to be a little more high spirited as well as mustangs. Quarter horses are a great all around horse to have especially for western riders.