I think they do have value, and you should certainly not dispose of them. If you are pondering whether you should post them on the web and identify the people, I would be a little cautious about that. There are many still-living people who are not fans of having old school photos and yearbooks online for anyone to view, and do not care to have their names and photos end up in an unknown data base somewhere. If those of your father's generation are all deceased, it may be OK to post their photos.
For photos with still-living people, I say create an index that identifies them, if you're able and it doesn't already exist, but leave the public revelation to the next generation. Just my opinion, others may differ.