* "html" added before "body" in the CSS
I like to apply styling to both. If needed, one or both elements can be styled separately too.
* Photoshuffler code removed - I'm having issues with this anyway, but I will need to either fix this or get a replacement as I want an album of pictures to automatically display on this page
I removed it because I was addressing your question about menu buttons.
* Some other "stuff" removed that came from Dreamweaver, such as text decoration, etc.
text-decoration is that line under the anchor
* More coding added to the img part of the CSS
I thought I commented on that. I don't have your images so I changed them from default inline to block level elements, then gave them a color so I could see them.
* Font size removed from header - is this needed at all here?
Font size is up at the top of the CSS. If the font size is different in #header, then it needs to be there but no need to repeat it there if it's the same.