It is hard to call a single breed as the best breed but I would like to mention the top ones here:
I would like to give the first position to golden retrievers in this list. They are not loyal, joyful and friendly but I also found them very smart.
Secondly, I am in love with this Askal breed because of its good temperament and good behaviour with kids. It is also easy to handle these dogs while travelling outside mainly for camping.
Bulldogs are also another love of mine. You can even raise them in a small apartment and they don't disturb you.