This question was asked on Creators, "...I want to change the font size for my Page Headers, but not the module headers."

The following CSS will change the font size for all page headers, for example: All new pages at /pages, Member Page, Blog, Forum, etc...

• Adjust the font size to suit your needs. I'm using 175% (1.75em) in example. You can use % or font size like: 16px
• When you're ready, add to bottom of CSS via Manage/Appearance/Advanced CSS.
• Save your code.

CSS:
.xg_headline .tb h1 {font-size:1.75em!important;}

Here are some screen shots. I made the font size very large in these examples, to show you what you are changing. You'll see:
1. Members page
2. Ning page like /page
3. Discussion page