Their easily fixed. I've found that the ads under the game screen pop up and take over the screen if you scroll the mouse over them. So to fix them I just adjust my screen so the lower ad doesn't show. I do that and 'm not likely to scroll over it and cause it's pop up trigger to go off.
I've had the pop-overads pop up, even when I haven't moused over the ad. It's all well and good to say just close them, but my computer is on the old side. Every time those things pop up, my computer bogs down. More often than not, I have to close the browser down all together, and start it back up. I don't play games to get frustrated.