Bringing a furry friend into your home is a special moment. Proper preparation will help make the transition smoother for all involved. Make sure you take the time to properly research the breed, check with your landlord if necessary, and commit to a 10+ year relationship.
Are you ready to adopt? Is your lifestyle such that you can spend time with your new friend? Or will she be locked in a crate all day? Life changes should all be considered before adopting: moving, new jobs, birth of children, etc. Will you still be able to care for your pet?
Once you have considered all these factors, you need to choose which breed is right for you. Your lifestyle and living space (plus how much time you spend at home) should all be considered before you adopt your dog. Research breeds (Retrievers like to run and spend time outdoors while Great Danes can actually be great apartment dogs) and ask the staff at the shelter for guidance in selecting a dog.
You will not see who this dog truly is until he or she is in your home for a few months. They will be insecure at first. They have been uprooted from where ever their home was and really do not understand why they found themselves suddenly in a cage or a strange foster home. Be patient and understanding. But also set your boundaries. I recommend getting a trainer as soon as possible to help you with the transition and creating a pack with your new dog. You must be the master, the alpha, for the dog to successfully meld into your family.
I think this is simply preference. I have had both male and female dogs. In my own personal experience, my female dogs were more nurturing to my kids. I do believe if you are a multi dog household it is most ideal to have one of each.