Thanks for the quick response!
I tried what you suggested and here is what I see:
I can't change either of those items. When I select the email address and click on it, it comes up in a dropdown list but there are no other selections.
Is there some other way to set my default calendar to the "device" calendar as you've suggested?
The device calendar seems to exist (items show up, syncs with Outlook, etc.) but I cannot add items to it from the BB and now it appears I can't even select it to change to it. It's as if the device calendar "doesn't exist" as far as the BB is concerned...