If you are frequent poster (means if you keep updating status, sharing etc), they will not get any notification but if you are posting something after a long time (3 weeks or more), they will get notifcation. There is no control.
If you are writting something on your friend's wall, only they can control who can see that. You can't do anything in that, it will be visible to all your friends.
If you are writting something on any Page, it will be public.
There is no privacy setting to control this.