I believe the only way to scroll text and have it validate would be to use javascript or flash. However, as I personally loathe scrolling text on sites, I don't know of any specific scripts that will do this. A Google search for javascript scroll text should get you what you need though if nobody has suggestions.

As far as the doctype, yes it does need to be specified on each page of the site. There is no global setting, and this tells the browser which mode to use when processing the page.

__________________
The best way to learn anything, is to question everything.
Interestingly Average Security Blog