Aw, please don't do that. I hate it when developers put flashy ad images in the screenshots section; I look at that section to see screenshots, and those types of images are distracting and annoying. There is plenty of room for features in the description.
I sympathise with you, but it's the only place a developer has to really get a potential buyer's attention beyond the icon, so the real estate is too valuable to give up! I think there needs to be a couple "raw" screenshots, but many successful devs recommend using that space to it's fullest potential.
There's a really good article out there about this that I can't track down at the moment, but here are a couple more that also drive the point home:
> Let’s take a look at an app that has done this well. Here we have Read it Later:
Look at Read it Later's page on a real phone and it's fairly terrible: the text is way too small and you can't zoom in, and again, it makes it more difficult to see what the app actually looks like, which is an important part of my buying decision. (There are screenshots within the "screenshots", but they are also rather small.)
For an easy comparison, Read It Later Free's page has only real screenshots, and I find it nicer.
It's definitely not just you. As a customer, I get quite annoyed when a screenshot tries to explain how the game works, as it becomes confusing which parts of the graphic are the game itself and which are not.
Maybe it's just me...