2
You can add a new block. with all items you like. The main menu could be desabled.
Block administration - add custome block. And add the html below.
<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td height="20" id="mainmenu"><a class="menuTop" href="http://www.xy.net/modules/support/">Menu1</a></td>
</tr>
<tr>
<td height="20" id="mainmenu"><a class="menuTop" href="http://www.xy.net/modules/support/">Menu2</a></td>
</tr>
<tr>
<td height="20" id="mainmenu"><a class="menuTop" href="http://www.xy.net/modules/support/">Menu3</a></td>
</tr>
<tr>
<td height="20" id="mainmenu"><a class="menuTop" href="http://www.xy.net/modules/support/">Menu4</a></td>
</tr>
</table>
hope it helps
Markus