Sounds to me like you want "conditional formatting". I don't use it very often, just enough to look it up when I want it, and the way it works has changed from Excel 2003 to 2010. But if you look it up in the Help files, maybe "conditional formatting" will get you to all the information you need.

If not, someone else here will be able to get into details with you. I think Pecoflyer is pretty familiar with it.