Hello,
Figure I would chime in, FWIW.
Laws vary from State to State and even from Jurisdictions within states so there is no one answer which would be 100% correct in all circumstances.
However, in the scenario presented where a person has stepped in front of your vehicle and others are attempting to open the doors;
I would say that you would be more than justified in driving away and even hitting the person attempting to block your egress. But, keep in mind that you are in a vehicle which outweighs the others by over 1,000 pounds so you do not need to drive very fast nor hit them with a great deal of force. You can simple continue moving forward at a steady rate of speed and if the guy does not move you will move him. As for legal justification, as long as you can convincingly state you feared for your safety you would most likely not have any problems. If you are a woman then you can get away with things even further.
Keep in mind that people have argued, successfully, in court for not stopping for marked police cars until they got into a residential area due to all of the police imposters out there now. So do you honestly think that a jury would convict someone who could show they were in fear of their life and drove away from a potentially dangerous situation?
Here is my disclaimer
While I am not an attorney I have been in court numerous times. I have worked as a Police Officer, PA State Trooper and am currently working for the GA Department of Public Safety. In all instances where you need to obtain an accurate opinion regarding the legality of any given situation you should contact an attorney whose practice focuses on the area in question. You could also try contacting the local prosecutors office but they will most likely not give legal advice and also refer you to an attorney.