Printing frames is browser dependant, handling frame printing in various ways.
With IE, you can right-click a menu link and select 'Print Target' or right-click the frame contents and select 'Print'
Firefox uses the term 'Print this frame' when using the right-click context menu for a frame link or the frame content.

If you are producing a site with printable content in mind, it might be just as easy to provide a link to a printable version of that page or a prepared PDF version for printing.