Want a dog you can dress up and put in cute clothes? Then look for a dog that has plenty of hair (for those fancy hair-dos) and is small enough to carry around. "Designer dogs" like Poodles, Yorkies and Westies, Bichon Frises, Pomeranians, and the more exotic Shih Tzu are excellent candidates for this.
If you're looking for protection, be sure to look at breeds that aren't too friendly to strangers. Great Danes are huge and intimidating, but they're likely to fall in love with the first burglar they meet! Bulldogs are another breed that look fierce but come out kissing. German Shepherds are probably the most familiar and trainable guard dogs. Other breeds also protect your home and family: Rottweilers, Boxers, Doberman Pinchers, and Giant Schnauzers are among them.
There are a few breeds that were created for their ferociousness. Rottweilers and Pit Bull Terriers are notorious for vicious attacks. So if you are considering these breeds, you must be very clear about what to expect and very careful in training a well-behaved dog.
When you decide to bring a dog into your home, you need to be educated about what you need, what you want, and what breed will most likely fulfill your goals. When you adopt a dog, you are adding a member to your family - one for which you will be responsible for a lifetime. You should be committed to working through all the behavioral and training kinks and providing a stable, loving home. You'll not only have to train your dog, but you'll have to be trained in how to handle that dog.
A final note: Cesar Milan, the Dog Whisperer, says, "There are no bad dogs. Only bad dog owners." No matter what breed you bring into your home, in the end, you are the one responsible for your dog's behavior. Learn all you can about the dog you hope to own, and learn all you can about yourself as a pack leader. Even the feared Pit Bull is a sweet loving dog in the right hands.
No matter what breed you think you want, you should know about the specific dog's parentage, personal history, and temperament before making the commitment to be his lifetime caretaker and friend.