Or you could take out the height= completely and the image would retain it's perspective. It was made for 800x600 resolution so at 1024x768 it looks like [this] (that is how it is supposed to look and it will look good at any resolution with this fix)
change your code to this:

Code:

<td bgcolor="#FFFFFF"><div align="center">[img]images/header.jpg[/img]</div></td>

I think you will like that.
this is what I changed:
td height="110" (I removed height="110")
height="140" (I removed height="140")