That's a movie-fu technique that depends largely on the camera angle. Sort of like the hook kick that appears to knock out two opponents at once.I've seen a variant of this attack in modern media used where an assailant grabs a person from behind and that person performs a high kick that hits the attacker in the face. Theres never a good enough angle to tell exactly which part of the foot is striking. I would assume the toes would be the the main mode of attack. that is if it landed at all.
You would need to hyper extend your leg to some degree to hit an opponent your height rather than overshooting.
This would also be necessary if you wanted to use the ball of your foot.
Does anyone know if this is an actual attack, or just another flashy move they use for comics and shows?
As far as a real front kick aimed at the head of someone in front of you, either the heel or the ball of the foot will work. Generally the heel works with more of a stomping action and the ball of the foot works with more of a snapping action to the kick.