con un annidamento di tabelle lo centri in orrizontale e in verticale :
codice:
<table border="0" width="100%" cellspacing="0" cellpadding="0">
  <tr>
    <td width="33%"></td>
    <td width="33%"></td>
    <td width="34%"></td>
  </tr>
  <tr>
    <td width="33%"></td>
    <td width="33%">
      <p align="center">filmato !</td>
    <td width="34%"></td>
  </tr>
  <tr>
    <td width="33%"></td>
    <td width="33%"></td>
    <td width="34%"></td>
  </tr>
</table>