It looks like the problem is that you are pulling in a background image for the div that contains the text that is 540px wide and your style code for the div has the width at 550px.

Ergo, text falls outside the right-hand side of the background.

Without looking to much deeper, I suspect that Firefox is actually doing things right and you got looky with IE.

If by saying that you want to do web design, do you mean the look-n-feel of the site or the actual coding of both.

If youare interested in the coding side, then I suggest you learn how to redo your site without using table as a layout tool, follow coding standards and get rid of non-standard items, be they html tags or css attributes.