Hi Kevin - building on Carolyn's suggestion, Reason's built in text
only pages load a print_styles.css file with an attribute media=print.
You may be able to edit this (or if you are running a current nightly,
place a local copy in www/local/css/print_styles.css) that hides the
page regions you want hidden. You could also modify the template to
load a print style sheet on every page if you didn't want it available
only on text-only pages.
For a more brute force method that didn't use CSS, you could modify
the template to not run various modules on print-friendly pages.
Reason templates have a method called alter_page_type($page_type). It
returns a page type array that maps modules to template page regions.
You could use this method to map the regions you don't want to an
empty string to turn off a number of modules when
(isset($_GET['printer']) && $_GET['printer'] === 'true').
Nate