I've heard of this code that you can use for your menu. If you made a change to one special page, all the menus would change, simalar to SSI. Its something like this:

<?php include="http://www.myhost.com/~michael409/menu.HTML" ?>

Is that correct? Should .html be .php? What else is wrong?

You need to take away the equal sign, and fine the full path to menu.html.
<?php include '/path/to/~michael409/menu.html'; ?>

This might work:
<?php include getenv('DOCUMENT_ROOT') . '/~michael409/menu.html'; ?>

With the include function, though, you should be able to include a url, if your web host has php 4.3.0 or newer installed.

http://php.net/include/