Does Getting Gets Fixed Calm Them Down?

Not necessarily.  Get the dog into a training school and train it..  

If you do not intend to breed from your dog, there are many advantages to desexing.  Desexing reduces roaming, aggression and breeding behaviour like mounting and urine spraying.  It prevents unwanted litters and has many long term health benefits and desexed dogs generally live longer than entire dogs.  Desexing eliminates reproductive diseases like ovarian and testicular tumours and cysts, pyometra, certain hormonal disorders, and reduces mammary gland tumours, mastitis, prostate disease and infectious diseases that are more frequent in animals that are more likely to roam, fight and mate with other animals.  

I have found that all of my dogs have chilled out when they got fixed...and they dont chew as much stuff either