If you are interested in a dog as a pet, getting a large one makes the most sense. You shall find other smaller pets when you prefer such kinds. You will also not miss smaller dog breeds for pets if that is what you want.
You need to make sure the dog has certain qualities about it. Friendliness is an important one. If you intend to keep it around your family, it has to be a friendly breed. You need it to be so, especially if you will be taking it to places where there are other people, like at the park. Where you get one that is also protective, you shall have found a great pet. You need it to be affectionate as well. You need a dog that shall be interested in being around your family, and even get excited at the prospect.
Look also for a hypoallergenic dog. You or someone else in the house may turn out to be allergic. Some people react so violently you have to let go of the pet. There are ways you can cope with those reactions, but it much more peaceful when you have no such reactions, to begin with. You need to get one that will not shed so much fur.
There is a need to get one that is loyal. One that is more loyal serves your needs well. Those that can serve as guard dogs tend to be the more loyal kind. At the very least, the dog needs to be loyal to you directly as the owner.
You need to then check their energy levels. You should go for a highly active dog only if your house, your family and your time allows for it. But if your house is such that there is limited room, or you do not have the time or family size to attend to such activities, then a calmer dog that can get by with minimal exercise is ideal. You need to think of a more balanced dog when you have young kids who also need physical activities in their day.
Check also the intelligence levels. Where the dog is intelligent, it shall not take long to train it. You will also not have to spend so much in maintaining it, and it will cause minimal loses. This also makes them better companions for your kids.
Focus also on one that is playful, gentle and self-aware, especially for families with kids. You shall find more info about large dogs on this website. Canine Weekly shall be your preferred source of more info on large breed puppy food, best dog shock collar, best hypoallergenic dog food, and such. You shall, therefore, discover more on the Canine Weekly site. You can view here all that and more.