I was ready with a reply, until I came to your last sentence. And that is take her outside, on lead, to gently and politely meet people/animals as they go by. It is true that you cannot introduce her to the whole world, and that strangers will still exist. However, the more people and dogs in the neighborhood she meets, the less strangers there will be, and the less barking and upset to the household. I know of many dogs (my Ginger included) that will bark at people/animals that they do not know. But are not phased when dogs and people they know go by. So you are right, you may not be able to end all barking from her, and you may not want to end all barking. Having a dog that barks when a stranger is around is not the worst thing in the world. You just need to take her out there and let her know which ones are friendly and not a threat to her neighborhood.