I. Choose your headlines from NON-SERIF fonts (like Arial, Helvetica, Verdana, Tahoma, Futura, Optima) & your body text from SERIF fonts (like Roman, Times Roman, Times New Roman, Georgia, Bookman).
II. ITALIC is designed to draw attention to itself by desirable quality of being hard to read. That’s why, in a block of readable text, it makes sense to highlight a word or a phrase by printing it in Italic.
On the other hand, a few authors print entire web or print pages in Italic! That defies the entire function of the Italic style. Each time you utilize Italic font, be alert that you are making your words difficult to read. Thus use it carefully, like adding sugar to your coffee.