Office 2007 applications that use the new ribbon interface do not
include a built-in ability to change back to the old menu interface.
But there are many third-party add-ins that allow you to do this (ask
Google). One of my fellow MVPs has developed an add-in for Word 2007 to
mimic the old menu interface... there are two versions, a free one and a
paid one with more features... see http://ribboncustomizer.com for more
information.