
To narrow down the field ask yourself a few questions:
- Do you live in an apartment or a house with a yard?
- Are you single or married and if you have children how old are they?
- How much time can you dedicate to a dog?
- Do you have other pets in your household?

A new canine addition to the family is worth the time and research.
http://www.iams.com/dog-breed-selector
http://www.petinsurance.com/healthzone/pet-articles/pet-breeds/Top-10-Dog-Breeds.aspx
http://www.babble.com/pets/10-best-big-dog-breeds-for-families/