i would have the actors stand as absolutely still as possible, then take 3 or 4 quick stills. then roto each thing individually (arm, head, legs, everything in the scene, etc) and use something like Elastic Reality or Twixtor (i HATE twixtor, though) to create the inbetweens. it would work, i've done that sort of thing on movies in the past, but sometimes a single shot will take a month of work. the snow would obviously be all CG. i know the new warping engine in AE is probably advanced enough to do it, as well, i just don't know if AE will let you put in control/reference splines the way Elastic Reality and Twixtor do. i don't think AE's warping tool lets you put in reference splines. i mean, you can do individual roto'ed sections, but ER and twixtor let you put in open splines specifically for matching up begin/end points.
i don't have ER at home, and its been discontinued for a long time, so i can't really show how to do that one. but i could maybe fudge something together using what i have. i don't know, we'll see.
oh, i just reread what you wrote and realized you were probably asking about the woman getting out of the car, not the kid standing in the snow. yeah, i'd shoot her on a greenscreen, it'd be pretty easy using ghosted frames, varying opacities, etc. the only thing that looks really hard about that shot is that the flashed stills of the woman are changing perspective as the camera moves, after
they've stopped moving. that would be hard, probably impossible with one video camera.
hmmmm... you could make 3d geometry of the woman in all the flashed poses and project the pictures on to it - then you'd have perspective changing! 3d track your greenscreen footage, and BAM! done! (well, it would be tons of work, but there it is in theory...)
does that all make sense?
see, anything's possible! Max + Photoshop + After Effects = whatever you want!