Welcome to DevShed Forums, jjohnson6353.
Are you talking about this page
For one thing, it looks like you don't understand how the comma works in selectors. It completely separates selectors, so you would need to restate the class if you want to apply a rule to multiple element types within an element, e.g. a <table>, that has a certain class.
Also, you probably don't need to include "tr" or "td" as a simple selector when it's not the "key selector" (which in CSS3 is the right most simple selector, and in these cases are "p", "h1", "h2", and "img").
I recommend you read these:
Grouping and Nesting
Many of the people who know CSS here are primarily developers, not designers, so I don't know if you'll get much in the way of design advice.
P.S. When posting code, please place it between [code][/code] tags