Don't have your model, but have a couple of other Olympus models. What I suspect is that the delay in the shutter release is laser focusing finding the range. On mine if you hold the shutter button partially down, a light comes on in the view finder to show you locked in the range and then continue to push down the shutter button the rest of the way to release the shutter.
On mine I can use it to take a Quick Time Movie mode. From there you may be able to capture the screen shot that you want.
I am probably all wet thinking this is the same on your model, but thinking the concept is the same.