I think I got it..
In tbopen put..
<div align="center" style="width: $width;" class="tablesurround">
<table cellpadding="{$theme['cellpadding']}" cellspacing="{$theme['cellspacing']}" width="100%" class="tableborders">
And in tbclose put..
</table>
</div>
Then put your values in the css. I was trying to pass em in the div tag before. Checked it in Moz, IE and Opera. One thing, if you have a fixed width for your div line add px to it $widthpx; otherwise if it's a percent then you do not need it. For those wondering why bother, it reduces the amount of nested tables which should make your page load quicker
