It sounds like you are understanding everything pretty well. You'll be able to teach us before long.
I think a lot of people post that 1/6 octave smoothing so that the graph looks prettier... it smooths the response line and eliminates all those little jaggies. I typically prefer to see the full resolution sweep myself.
EDIT: I just noticed JohnM posted about something similar on your soundcard issue
here. It might help you, but I think you are okay anyway.