There appears to be some absolute positioning going on on the iframe that google includes (#google_ads_frame). This is set to left: 0; and top: 0; though, so it shouldn't be displayed where you show us in the images. I don't have a machine with IE7 installed right now, so I wasn't able to check properly, but I did go through the ad code, and that is the only place I found position: absolute. Not having used Google Ads before, I really don't know what kind of configurations you have available to play with, but I hope you find a solution :)
Jesper Karsrud
2009-07-05 11:47:45