Newbie question about organizing

[RonA]

Hi, folks. Brand new here.
I have several thousand photos that I am starting to organize for our local historical society. Right now, the photos are in folders named for the person donating them, or some other mass grouping name. I would like to eventually put all the photos in one large group, so that a search would cover the entire collection, and not just one folder. I was thinking of creating an "album" for each folder, so our current organizational structure would not be lost, but rather incorporated into the whole collection.

I hope that made sense. To you experienced users, what would you suggest we start with? I have an entire list (and growing) of categories to use for the metadata tags.

Thanks very much!