1. fix your filler image and remove the gray line at the top of it.
2. Use something like this in the template.
Code:
<!-- logo -->
<a name="top"></a>
<table class="header" width="$stylevar[outertablewidth]" border="0" cellpadding="0" cellspacing="0" align="center">
<tr>
<td align="$stylevar[left]"> <a href="$vboptions[forumhome].php$session[sessionurl_q]"><img src="$stylevar[titleimage]" border="0" alt="$vboptions[bbtitle]" /></a> </td>
</tr>
</table>
<!-- /logo -->
3. Do something like this for the css bg call instead of using a call in the table or with another td, put in as another added css call in the style manager.
Code:
.header {
background:url(/forums/images/logo/bg.jpg)
top repeat-x;
}