Making all points meet in the middle using inset I have a cylinder that I want to close the tip by making all the points meet in the very middle. Kind of like what I have here but further inward meeting to one point in the very center. When I press I and then 0 (which I thought would bring them all to meet in the center) nothing happens.
You want to use the Merge at Center operator.  You can find it on the menu, or by pressing Alt+M or search for it using Space.  You will see more options.