codice:
<?php 
include("menu.html"); 
?>
Va benissimo a condizione che il tuo server ti abbia abilitato l'uso di PHP

Oppure in javascript
Pagina dove includere il menu
codice:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Documento senza titolo</title>
</head>

<body>
<div id="menu"><script language="JavaScript" src="menu.js" type="text/javascript"></script></div>
</body>
</html>
File esterno "menu.js"
codice:
// JavaScript Document


info="<table width=&#34;1000&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"  <tr> " + 
"    " + 
"    	<table width=&#34;184&#34; border=&#34;0&#34; cellpadding=&#34;0&#34; cellspacing=&#34;0&#34; class=&#34;fondmenu&#34;> " + 
"        	<tr> " + 
"            	<td class=&#34;fondmenu&#34;> " + 
" " + 
"						<table width=&#34;173&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"						  <tr> " + 
"							<td style=&#34;padding-left:1px;&#34;> " + 
"							<div class=&#34;menuhaut&#34; id=&#34;menu_toogle_0&#34;>Il sito</div> " + 
"						  <div id=&#34;menu_content_0&#34;> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/inscription.cl&#34;>Iscriviti</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/visiteguidee/&#34;>Visita guidata</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/equipe.cl&#34;>Lo staff</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/historique.cl&#34;>Storia</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;http://forum.codelyoko.fr&#34;>Forum</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/liens.cl&#34;>Link</a></div> " + 
"						<div class=&#34;menubas&#34; id=&#34;menu_close_0&#34;> </div></div></td></tr> " + 
"						  </table> " + 
"						
 " + 
"						<table width=&#34;173&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"						  <tr> " + 
"							<td style=&#34;padding-left:1px;&#34;> " + 
"							<div class=&#34;menuhaut&#34; id=&#34;menu_toogle_1&#34;>Le D.A.</div> " + 
"						  <div id=&#34;menu_content_1&#34;> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/newscl.cl&#34;>News CL</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/histoire/&#34;>La storia</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/monstres/&#34;>Mostri</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;java-script:alert(&#39;De retour très bientôt !&#39;);&#34;>ciao</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;java-script:alert(&#39;De retour très bientôt !&#39;);&#34;>Programmation</div> " + 
"						  <div class=&#34;menubouton&#34;>Avis sur le DA</div> " + 
"						<div class=&#34;menubas&#34; id=&#34;menu_close_1&#34;> </div></div></td></tr> " + 
"						  </table> " + 
"						
 " + 
"						<table width=&#34;173&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"						  <tr> " + 
"							<td style=&#34;padding-left:1px;&#34;> " + 
"							<div class=&#34;menuhaut&#34; id=&#34;menu_toogle_2&#34;>Le vostre creazioni</div> " + 
"						  <div id=&#34;menu_content_2&#34;> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/fanfictions/&#34;>FanFictions</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/fanfictions/categorie-10.cl&#34;>Canzoni</div> " + 
"						  <div class=&#34;menubouton&#34;>Coloriages</div> " + 
"						  <div class=&#34;menubouton&#34;>Autres</div> " + 
"						<div class=&#34;menubas&#34; id=&#34;menu_close_2&#34;> </div></div></td></tr> " + 
"						  </table> " + 
"						
 " + 
"						<table width=&#34;173&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"						  <tr> " + 
"							<td style=&#34;padding-left:1px;&#34;> " + 
"							<div class=&#34;menuhaut&#34; id=&#34;menu_toogle_3&#34;>Plus !</div> " + 
"						  <div id=&#34;menu_content_3&#34;> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/garagekids.cl&#34;>Garage Kids</div> " + 
"					        <div class=&#34;menubouton&#34;><a href=&#34;/howtodraw.cl&#34;>Come disegnare...</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/subdigitals_us.cl&#34;>Subdigitals US</a></div> " + 
"						  <div class=&#34;menubouton&#34;>LyokoQuizz</div> " + 
"						  <div class=&#34;menubouton&#34;>Sondages</div> " + 
"						<div class=&#34;menubas&#34; id=&#34;menu_close_3&#34;> </div></div></td></tr> " + 
"						  </table> " + 
"						
 " + 
"						<table width=&#34;173&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"						  <tr> " + 
"							<td style=&#34;padding-left:1px;&#34;> " + 
"							<div class=&#34;menuhaut&#34; id=&#34;menu_toogle_4&#34;>Galleria</div> " + 
"						  <div id=&#34;menu_content_4&#34;> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/groupe.cl&#34;>Gruppi</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/ulrich.cl&#34;>Ulrich</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/yumi.cl&#34;>Yumi</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/xana.cl&#34;>XANA</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/secondaires.cl&#34;>P. secondari</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/lieuxterre.cl&#34;>Luoghi della Terra</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/lieuxlyoko.cl&#34;>Luoghi Lyoko</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/galeries/decors.cl&#34;>Scenari</a></div> " + 
"						<div class=&#34;menubas&#34; id=&#34;menu_close_4&#34;> </div></div></td></tr> " + 
"						  </table> " + 
"						
 " + 
"						<table width=&#34;173&#34; border=&#34;0&#34; cellspacing=&#34;0&#34; cellpadding=&#34;0&#34; align=&#34;center&#34;> " + 
"						  <tr> " + 
"							<td style=&#34;padding-left:1px;&#34;> " + 
"							<div class=&#34;menuhaut&#34; id=&#34;menu_toogle_5&#34;>Goodies</div> " + 
"						  <div id=&#34;menu_content_5&#34;> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/goodies/ss.cl&#34;>Screensavers</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/goodies/bootscr.cl&#34;>Schermate di avvio</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/goodies/logonscr.cl&#34;>Logon Screen</a></div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/goodies/curseurs.cl&#34;>Cursori</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/goodies/skins.cl&#34;>Skins</div> " + 
"						  <div class=&#34;menubouton&#34;><a href=&#34;/goodiesmaison.cl&#34;>Goodies maison</div> " + 
"						<div class=&#34;menubas&#34; id=&#34;menu_close_5&#34;> </div></div></td></tr> " + 
"						  </table> " + 
"						
 " + 
"						" + 
"						  </td> " + 
"            </tr> " + 
"        </table> " + 
"" + 
""

document.write(info)