@John: Order Printer has better default templates, a cleaner interface, a better code editor, more forgiving template editing, and can print documents in bulk. It will also be one of the first Apps to be embedded within the admin. We couldn't have done most of this without significantly updating the application, like we have with Order Printer. And we have a lot more planned!
To deselect a template by default, click on the "edit" link beside it's name and scroll down below the code editor. You should see a checkbox labeled "Select this template for printing by default". Unselect that and you're good to go.
We're shipping a change this week that will simply remember which templates you've selected. It's a much simpler solution with no hidden menus.
I hope that answers your questions!