In either case, don't expect great results. The image area on 8mm film is tiny: about 1/32 of that of 35mm film. You will get quite visible grain, even on prints of moderate size. Furthermore, individual frames of movie film often show motion blur which is not objectionable when viewing the movie, but can be an issue here. The perceived amount of detail in the picture is much greater when the frames are shown in rapid succession, as intended, than when you pick out one still.
When I was still working and EK was processing , the largest
they would do from any movie film was approx 2 ¼ X 3 ¼
and the results were not always that good due to all the reasons posted above.