div align="center">

  <table width="760" border="0" cellpadding="0" cellspacing="0">
    <tr>
      <td width="760" height="100" valign="top">Logo</td>
    </tr>
    <tr>
      <td width="760" height="400" valign="top">

<!-- The nested table begins here. -->

       <table width="760" border="0" cellpadding="0" cellspacing="0">
         <tr>
           <td width="200" height="400" valign="top">Nav</td>
           <td width="560" height="400" valign="top">Content</td>
         </tr>
       </table>

<!-- The nested table ends here. -->

      </td>
    </tr>
  </table>

</div>