All we did was move the ads from the middle to the top. The size really did not increase for we removed a 250x60 ad. (We used to have a 468x80 and a 250x60 with a 15 pixels spacer side by side. (thus 733 pixels wide)
The result is that the we actually moved the site up on the screen more and not lowered it. If we move the ad back down, the site will drop down on the screen also. But the ad size is actually smaller in width.
Thus we actually have less ads on the site in total count.
"P.S. Also annoying are the pop-ups in IE about needing to install Adobe Flash Player."
This is not something we control as it is your choice as to the browser and the install of what you choose to run. Flash is the way that ads are going on sites. It is not just AVS, not by along shot. Just install the flash player.