Thanks for your help. It wasn't exactly the solution I was looking for but did get me on the right track. Here's what I have so far. I've removed some irrelevant code for this post.
<div class="hold" align="center"><img src="brand_cov01.gif" alt="Green Cover" name="brandcov" id="brandcov" width="147" height="313" border="0" align="middle"></div>
Everything almost works as it's supposed to. The image I have in the div tag is centered horizontally but not vertically. Rather, it's aligned to the top center of the browser window. My overall goal was to have it in the center of a browser window no matter how wide or narrow, etc. Ideas on how to have it vertically in the middle?