Similar to what Frank62 might (vaguely) be suggesting, have you tried defining a height and width for the divs? Not knowing what's in the scripts (I would guess they are banner ads of some sort), they also might be throwing something else into the works that we can't account for.
Also, at this point in time, don't even waste your time with IE6. It's 10 years, and three (almost 4) versions old. Anyone still using it deserves every broken page and malicious security exploit they come across, if only for their own sheer ignorance. If you have a way to gracefully tell them to "F off" in the process, then all the better. I can still understand the need to "re-develop" for IE7.