Just use this...
set up a folder structure like this...
|-pages <this is a folder
|-images <this is a folder
now write your index page like this...
$page = $_REQUEST['id'];
print "<html><head><title>My Page</title></head>
so you see... now when you open the site, index.php displays the menu file and the contents of the main.html page...
if you go to index.php?id=news
then it'll display the news page from the pages folder.
(it also has that addes bonux of only having one menu file to update as well...).
When you write the html pages, write them as if they were in the root folder as well...
so to link a picture just put <img src="images/test.jpg"> not <img src="../images/test.jpg">
because the page is rendered as if it were a part of the file index.php since it's called from that file.