My little pup doesn't bark very often and he's totally friendly, but what I do with him might help you with your door problem.
I keep my front door locked so that everyone has to ring the bell (even family if I'm expecting them) and can't just walk in (I don't want my little dog running outside).
Then - whenever the door bells rings. The first think I do is find my pup, pick him up, and carry him with me when I answer the door. I also hold onto him for the first few minutes after anyone comes in. If you do this, your little dog would know who's there and be a little less excited when you put him down.
Good luck! |