Since you're considering having children soon, I'd be wary of some of the breeds mentioned. My recommendation would be a Golden Retriever, they're extremely loyal, love to please, and are GREAT family animals. They are active dogs, will need a large yard and lots of exercize - they love the water be it a river/beach/lake and are great to take on trips.
Regardless of which breed you ultimately choose, do some research first, quite a few breeds tend to have certain genetic traits that you may need to be aware of, and check for the proper papers/tests when selecting your dog. When you decide to purchase your animal, try to find someone reputable, while staying away from the "backyard breeders", going back to what I said before about specific genetic traits for indiviual breeds - a good breeder will often have several generations of paperwork and SOME genetic traits can be "bred out" so to speak. Your dog will be an extension of your family, so it's not something to take lightly 
 
Also to those who are suggesting labs - I'm also a lab fan, they're great dogs as well and share many traits with goldens.
Good luck.
PS: One more thing, if you find yourself attatched or attracted to a certain breed - you might consider looking for breed specific rescues in your area, even if you decide to get a puppy instead of adopting, it's a great way to spend some time with the breed and get even more info 
 
EDIT: Bah, I missed the part where you said you were gonna go to a reputable breeder - don't mind me I can't read :/