Growing up I would spent lots of time at my grandparents house. Living there was my great grandmother that was born at the turn of the century. It was always refered to as tonic, if I was mowing the lawn and it was 150 degrees, it was a tonic that I was offered, not water.
My family did not say "pop", but I knew a few that did. Now it is soda for me, but I rarely request it that way, mostly it is a Mountain Dew or Coke or Cherry Coke.
My thought on the "cella" is this, being right around 6 feet tall I can't stand up straight in my grandparent's "cella", I can however in my basement.
The porch has always been a porch for me as that is what my grandparents called it. And I will tell you one thing, if your screen door don't creek when it opens and slap when it shuts, you ain't from around here.