The best way to do this, in this day and age, is to digitize all the old photos and put them somewhere on the internet where family members can comment on them.
So, how to digitize them!
The 4 Ways to Digitize Your Precious Photos:
Camera: I know it's strange to start a scanning discussion with "don't scan them", but with today's digital cameras and latest smartphones you can do a decent job of digitizing an old photo by just taking a picture of it. In fact, the really professional operations who are digitizing all the known records around the world use a camera set-up. At least 12MP.
A Service: Also, nobody has time to deal with this. There are many services that will scan your photos and clean them up a bit. A good one is ScanCafe.com, and there are others. The nice thing about these services is that they do slides (remember those) and just about anything you can put into a box and send them.
|Canon CanoScan 9000F Mark II|
Scanner: a decent flatbed scanner is actually not that expensive anymore. There are really good ones under $200. You just need to make sure you scan at least 600 dpi, going up to 1200 dpi for small images.
And now share them!
The importance of sharing these photos can not be ignored. That old picture of your great grandfather means something incredibly special to possibly hundreds of people. Share it. And likewise, you'll be astonished that people have photos you never knew existed.
Create a Facebook group private to your extended family, or post them on Google Photos and send out links.