Firstly, you would think in this day and age that a 61 year old disabled man with a heart condition would be safe in his OWN driveway, but you would be wrong in that assumption.
Here, David Sprowl of Fort Wayne, Indiana (with oxygen tank in tow) pulls down his driveway on his motorcycle on his way for an afternoon ride when a gang of black thugs are fighting in the street in front of his home. After threatening to call the police, one of the male thugs sucker punches Sprowl, knocking him to the ground and injuring him seriously.
Hindsight is always 20/20 in a situation like this, but regardless if it is your property or not, NEVER walk INTO a situation like this (ALWAYS keep your distance) and NEVER go unarmed. If they refuse commands to disperse, call 911 and wait. If they approach you in a threatening manner or trespass on your property, defend yourself accordingly.