Part of my grand scheme includes some form of labeling. At this point I have many ideas but no solid plan. First, there would be a universal unique file naming/numbering convention so I can refer to a photo deterministicly. Several photo formats allow metadata tags which I would use. I would probably have a folder for each roll of film and put text files in each with my best guess as to when and where the roll was taken and who has the original negatives and prints at this date. I figure on a master database format to refer to individual photos for "this is Tom, Dick and Harry" type information, but I want that info duplicated in text files in that photo's roll folder.
I doubt I'll have to reinvent the wheel, though. There are online archives like photo.net, some of which are run on open-source software I believe, so I expect I'll be able to find a software package or at least a framework to enable me to do what I want.
Unfortunately almost none of my photos have info written on the back of them. At least on many rolls I wrote the date and location it was shot, so that will help. I don't think many of my old family photos have much info on them, either, which is kind of another motivating factor in starting this project: touch all photos and get info on them while people are still alive.
I'm also concerned about the archival value of digital photos. I am a skeptic about the 100-year CD-R or DVD-R. Ideally the whole collection should be copied to new medium every few years, but who's going to keep up with that? The file storage format is a concern, too, but I'll be sure to use openly defined formats (TIFF, PNG, JPEG and others as appropriate) which should minimize the chance that nothing will understand it in 50 years. Handing out copies of everything should increase the odds that some of the media survives. I certainly don't plan on trashing the original prints or negatives, and I plan to write my universal naming scheme identifier on each roll of photos so they can be located via my electronic versions.
I'm a film fan, but it hit me the other day that I would look at them much more if they were on CD or my hard drive instead of in a box in my closet, and I could increase the distribution of all my family's pictures. Plus my new HDTV revives my memories of slide shows, but this time I won't need to set up the screen and projector and keep turning and flipping slides.
If I do this, I'll probably try to identify photos that should be given special attention and printed archivally at a chemical photo lab: the occasional lucky masterpiece, family portraits and something to add flavor, depth and life to the photographic story.
By the way, most color prints and negatives fade. The old silver halide B&W film & prints will largely last a long, long time. (Many recent B&W films use the C41 process that color films use and aren't archival.) You can make long-lasting color prints, but you have to use the right paper and chemicals. I'm fuzzy on color slides at the moment...I was going to say some color slides last, but now I think it is the positive print process that's archival. Some color slides definitely fade badly.
EDIT: I've heard in tropical climates there's a problem with fungus or bacteria eating the glue holding the CD-R together and as a result corroding the data layer.