Having a dog is a fantastic way of keeping fit as you need to take the dog out for walks all the time, much better than any gym membership, the dog has to have a walk, no ifs or buts.
Dogs are very loyal and loving, no need to have a fierce breed at all, so many lovely breeds. We live in a frum area and some of our neighbours were taken aback when we got our dog, now their kids come over to play.