First thing I gotta say is this effect is not any simple little drag on preset in your NLE program, it involves a good little bit of compositing.
The background isnt moving behind the stills, the stills are moving with the background which tells you its definitely tracked. So this is how you would attack this (Assuming you have after effects and know it enough to be somewhat proficient in it):
Make the clip you want to do it on into a new comp. Create a null object and motion track something in your background and apply that tracking data to that null. Now just duplicate your main clip a whole bunch of times to make each of your still layers and turn off the visibilities of all of them accept the one you are working on and your background layer (work from the bottom up and leave the bottom most layer as is for the BG, lock that layer so you dont mess with it)
Now go to each point in time that you want a still to appear and (working from the bottom up) select a leyer and right click and go to time>freeze frame. Then go in and make a mask around the rider in that shot , just a square will probably work (with the layer selected you can use the rectangle tool at the top to make a mask, or you can draw it with the pen tool, just make sure that layer is selected) and feather the edges a bit. Now also at this exact spot in the timeline you need to link the still you just masked to the null object so it will stay where its at at that point. Also drag the clip in your timeline so it starts right at this point too.
Do that however many times you need and that should be it.
The thing is with this stuff is there are probably a whole bunch of different ways to attack it and this is just how I would do so. I know the guy that makes these is really good at compositing so dont feel silly is yours doesnt look as good as his on your first try. And this particular effect is not the easiest one to achieve if its your first time trying something like this.
Also if you have After Effects but dont really know how to use it then go to:
http://www.videocopilot.net/basic/ and take their free basic training, you can essentially do anything you need if you learn that stuff.
Good luck man!