After you go into the Preferences->General page tab, make sure that you are viewing the "Project Defaults" and not "User Preferences." Those two values are on the left hand side of the screen under the Preferences Level heading. Well, at least in 7.2.2 they are, I'm not sure if 7.2.0 is different. They are above the Preferences heading. If that doesn't work, perhaps someone else can help you.
HTH,
Nate