I can tell you what I have done with the 2000-plus photos in my computer.
I save the photos to My Pictures.Inside that folder, I have a folder for each Surname.When I scan a photo, I name it according to subject, date if known, event if known dot initials of person who provided the photo.I save all of my photos as JPG files.I save all of my scanned photos to the appropriate surname folder.
On the dates, I don't use DD MM YY.If a month or day is not two digits, I don't put "0" in front of it, but I do use the entire year. We are dealing with photos from, say, 1902 and 2002, and some of the names are very similiar.
I set up other folders within the surname folder for the different divisions of the family. For example, my g-grandparents had nine children.Photos exist for them and their families for eight.So I have a folder for each of those children, and inside those folders might be other folders for each of their children.
You can have as many folders inside other folders as you need to get the job done.You can also copy any photo from one folder into another surname folder if you want to do that.I don't do it because I think it is a waste of space, but if you have a large group of people, for example, and one of them is your ancestor that you want to have in her folder as well, you can copy it into that folder and still leave the group photo wherever you decide to keep it.
If someone emails a picture to me, I name them and put them in the appropriate folder at the time I save them.
On a couple of occassions, someone has sent a CD to me that has a lot of photos on it, and they want the CD back.In that case, I save the photos to the correct surname in a folder named "from _____"Then I can work through them as time permits, keep the ones I want to keep in the computer, and commit the entire folder to CD for storage.I then delete the ones I don't want to keep in the computer.You could do something similiar for scans of entire albums.
I have wills and other scanned items in these folders, as well.This keeps almost everything together in one place.Only the details and written family histories is kept in a "Genealogy" folder under My Documents, which is also in folders according to surnames.
This might sound like a lot of trouble and to-do just to file photos, but I assure you, it is worth it when you have as many photos as I have, and I have not scanned all of them yet!
One other thing ... when you make a sizeable addition to your data base, be sure to back it up on CD or DVD.Even if only adding a few photos, the data should be backed up at regular intervals.I make two identical DVDs every time I back up.I keep one here, and I give one to my sister who serves as my "off premises" archive.
Sorry for the length of this post, and I hope it makes sense. Good luck.