There's nothing wrong when I view them in safari, chrome, firefox, IE5, IE6, IE7 and IE8, except for the Media page.
When i run just the media page through the validator it throws up 48 errors, including unable to determine parse model.
This might be becasue you only have half th edoctype declaration
it should be
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
but the page only has
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
So try editing the doctype to the full code. Also do this in some primitive text editor, as the validator mentions unicode as you have the outer page in charset=us-ascii" so try setting
ascii everywhere