Quick time events are option screens that appear for only a few seconds. These usually require you to choose which direction to take, but sometimes can be used to choose an item.
In Escaping the Prison, two guards come up to you, and you have to click to left and right to hit them with the cell bar.
Where henry is going to ram etc. with his scooter in Stealing the Diamond, it is the only quick time event, which involves the keyboard.