You'd need one row that spans two columns for the image, and then the two columns beneath that. So:
<tr><td colspan="2">image code here</td></tr>
<tr><td>column 1 info</td>
<td>column 2 info</td></tr>
You'll also notice there is a lot of Smarty built in, which is what X-Cart uses as the template engine. This creates a lot of if/then statements, which can also affect that table layout. I'd suggest reading this and perhaps learning a bit more about Smarty first:
http://forum.x-cart.com/showthread.php?t=21529