My goal is to manipulate the text-styles of my application via DependencyProperties. I got a diagram in which the texts are to be manipulated in size, fontfamily, color, etc. So
ItemsSource here expects a collection; e.g. Fonts.SystemFontFamilies
Actually, here's a very nice link covering font selection:
http://www.hanselman.com/blog/LearningWPFWithBabySmashCustomerFeedbackAndAWPFFontComboBox.aspx
Scott Hanselman even shows how to render each font item in combobox with it's own font family.
Added per OP comment.
Here's an example of binding to dependency property. Property is named "MyFontFamily" to avoid collision with existing Window's property. Sorry, no Ribbon controls (I have bare 3.5 sp1).
Window1.xaml
Window1.xaml.cs
public partial class Window1 : Window
{
// ...
public static readonly DependencyProperty MyFontFamilyProperty =
DependencyProperty.Register("MyFontFamily",
typeof(FontFamily), typeof(Window1), new UIPropertyMetadata(null));
}