The key concepts of a printer friendly page are that it has no set table width (so the browser can flow the page the way it wants to), no frames (because users get confused about how to just print part of the frame), that it has no background colors (black text on a white background is ideal), and that it has no or limited graphics.
The lack of a defined table width and frames are huge because they're the two things that keep the screen image from fitting on a piece of paper.