You need to do this because viewers might enlarge the Netscape window. Your text will then stretch from one side of the screen to the other, if you haven't inserted a break or otherwise formatted your text. On the other hand, viewers may have small computer screens. If your graphics are important to the text, make them small enough to fit on the screen with the words. Avoid italics, especially if your audience will be using Macs.
Italics are hard to read.
Even the links are bolded, so as to be legible to children. Speed of Loading Graphics will slow loading. Use only one or two graphics for now, and choose them carefully. Remember that each design element you add should have a purpose. Keep the file size small for graphics.