The reason for some of the strangeness is that the page template was originally intended for a client who wanted a simple website but knew nothing about HTML. The plan was that I would deliver him some templates, fill in some of them for him, and provide instructions on how to update and add new stuff himself. So the comments, for example, are there to give him an idea of what each part of the HTML does, so that it would be easier for me to tell him "OK, to add a link to the navigation, find the list of navigation links (clearly marked in a comment)..."

Why Peter didn't take them out is beyond me. I shall have to berate him on IRC now.

Your comments about the padding are probably correct... if I were redoing the template now I'd probably just use ems everywhere. Also, I seem to recall doing something to make the picture have the correct margins, I'll have to find the original again and see what that was.