Just slightly toasted, so it wont fall apart, especially if i'm making a sandwich. If I'm using it just for PB, then not toasted will do.
Depends on what I am eating. If it's at home, I will go untoasted all the way (as long as the bread is fresh-ish). At Subway, I will go toasted.
What meal? To eat with what? Who is preparing? What kind of bread and what quality? Not enough information to vote.
For what, exactly? I'd eat it not toasted by itself, toasted and with butter or garlic for pastas and other Italian dishes, etc.