You can change the paper size (from US Legal to US Letter, for example) using the Customize window for the form you want to change. See To change the paper size used for your forms for details.
This tip applies to:
Review 1099 Forms Before Printing window
Review Checks Before Printing window
Review Labels Before Printing window
Review Purchases Before Printing window
Review Sales Before Printing window
Review Statements Before Printing window
Review W-2 Forms Before Printing window