I believe most sponsor ads are done with layers or iframes, which is probably why it looks funny when you put it in a table.
You may want to put the ad in the table with the logo, like you had in the second example, and then play around with the placement of the new topic buttons and that list of links... maybe try giving them a separate table cell under that or something...
Just for kicks and giggles, can you post the code for your ad banner? I can see what I can come up with by sticking it into a template myself...
---Skorpion
