It looks as though your dog just needs to learn a few  basic manners and door etiquette.  Because she seems to have “perfected” this behavior, I think the best way to initially address it is with some aversive training. Find something you can use that makes a fairly loud or startling noise (a can with ball bearings or similar will be fine or an air horn - you can also buy training aids of this type from pet stores).  Either carry it with you or leave it somewhere that it can be immediately accessible by anyone entering the door.

Whenever someone enters and the dog starts heading towards them, shake the can to startle her (this should snap her out of the instinctive behavior pattern she has learned).  When she is quiet, call her to you and pet her.  Once you have successfully stopped her from making a mad dash to yourself and visitors, start to teach her that she must sit still in one place when people come into the home (or room).

Enlist the help of a friend to play visitor and get them to knock at the door.  Ask the dog do sit and stay while you either answer the door or call them in.  If you need help teaching the Sit and Stay commands, there is some really good instructions in both written and audio format in the Sit Stay Fetch course from Kingdom of Pets.  to visit their website, click HERE

Once she gets used to how she is supposed to act when people enter the house, it will become second nature to her.  Remember too that spanking the dog will not get the results you want.  Praise and the occasional treat when she does what you want will be much more effective.