First, you have 10 independant stylesheets there, so you'll have to be sure to check that you're not getting redundant definitions fighting each other.
Second, "MsoNormal" does not usually occur in Zen Cart. It's a bit of "crap" (a technical term) from Microsoft applications, perhaps from Word. When you create something in Word and save it as HTML it comes out with all sorts of "crap" in it which has to be stripped out before you can use it anywhere else.
Third, do you have a good text editor? And a local copy of the unmodified Zen Cart? I found 14 instances of "Conditions of Use" in v1.3.8a. The one you most likely need to change is in ../includes/languages/english.php
I presume the style you want on your Conditions page is the blue headings seen in Shipping Info? If so, I see that you have an in-line style on the Shipping Info page, but the similar in-line styles on your Conditions page don't have any values filled in. I'm guessing you added those styles in define pages, so go there and fill in the values.
Incidentally, you don't need to use in-line styles there. Simply enter the text as <h3>Some heading</h3> and then set the style definition in your main stylesheet.
Rob