Get a mutt you rescue. Or, you can go to Hearts United for Animals at HUA.org and rescue one of theirs. They have purebreds as well as mutts. This is a wonderful charity; the family that started it has devoted everything to saving dogs from puppy mills and they care very much about dogs. I have adopted 2 dogs from them and they were both amazing pets. As to breeds, Chihuahuas are very loyal to one person, so if you want an "exclusively yours" lap dog, this would be a good one. They are small and easily injured by small children, so they work best with kids over 13 years old. I love this breed. Medium sized dogs that are very amiable are Lhasa Apso or Shitzu. The problem for me with large breeds is their short life expectancy. Mastiffs are only expected to live around 8 or 10 years..not long enough for me, I want my furbabies to live forever. And, Mastiffs have lots of health problems. Here is a site that tells you about them, and will tell you about many breeds. http://www.petmd.com/dog/breeds/c_dg_bullmastiff?utm_source=bing&utm_medium=cpc&utm_term=Bullmastiff&utm_campaign=Dog%2520Breeds#.UEzqE7JlQTY
If you're looking for a very large dog, get a mastiff, English or bull. I prefer the English. Both are extremely calm, wonderful with kids, great guard dogs, and very loyal and loving. Amazing with either large or small families. If you're looking for a more hyper one, go for the golden retriever. They are such good, obedient and healthy dogs. They love to be active! Going for a small dog? Well, you probably aren't going to find many calm ones there. But for the most part, Welch Corgis will always be an amazing companion, not bad with children either. Hope this helps! And good luck finding your new friend!
In my opinion, i think you should get a German Shepard. They are very out going, protective and loving. But if you want a small dog, get a yorkshire terrier. They are also very loving, and the dont shed.