Some help required with video/photo editing

TRAIL CAM PROJECT (National Trust / Cotswolds aonb) :We are looking for some IT help: Later this year the hundreds of videos and photo’s made with the grant-funded trail cams have to be edited into a 12-15 min. slideshow so the NT can use it in its visitor centers in The Cotswolds. The project deadline is the 31st. October 2016. The vision is that the slideshow will be on continuous loop on an old laptop, so multiple copies of the slideshow have to be produced for the NT on a Memory Stick or DVD. We will also make the slideshow available on this site, and hopefully it will appear on the Cotswolds AONB site as well, and various linked FaceBook accounts.
Does any of you have the right software / experience to produce this, using the stills and video’s which are being uploaded on the NC-DMG account on DropBox? Any advice/suggestions welcome. We’re not looking for BBC 1 Wildlife standards, just a reasonably watchable slideshow showing deer and other wildlife. Members who are interested in a preview of the (so far unedited!) Data are welcome to do so, please email us requesting a Link.