HOW DO I CHANGE THE FONT & COLOR IN A TEXT BOX IN ADOBE ACROBAT 8 PRO AND ALSO SET THAT AS THE NEW PREFERENCE OR DEFAULT

Assuming you are referring to a Comment Text Box, you can open up your Properties Bar (Ctrl/cmd-E).  Once you create your text box, you can either click on the box (for the box's stroke & fill), or double click to highlight the text, and adjust the color/properties in the Properties bar.  Somewhere in there (it's been a long time since I've worked with version 8 - maybe right-click on the box and select Properties) is a check box to set the current properties as default.  Once that is set, all others created afterward should have those properties.

I hope this is helpful.

My best,

Dave