Capture Still photos from Videos

I have about 3 hours of videos of an event that we held last year, that I want to showcase WHO came and WHO sponsored in a photogallery.? I need to have someone capture still? photos of the people, individually, smiling and happy, to show what a good time was had by all, and save as jpg.? Don't bother with the backs of people's heads and miscellaneous junk that makes for boring photographs.? An automated program to catch every few seconds of video will NOT suffice.? We need to get the BEST? pictures available, even though the quality is not so great.? I also need all the sponsor logos captured and saved as JPGs as well, so that my sponsor potentials for this coming year's event will see the photo gallery and realize what good value it is for their money.