By the way, renaming a photo using values from the ‘time taken’ attribute of the file is a pretty simple task using BulkRename utility.
Though I have started arranging photos in directories as per year and month, I did not follow this method in my initial days of digital camera ownership. On purchasing the camera, I tended to rename each file with a meaningful name. For example, a photo taken in London Picadilly Circus was renamed as such. I did this so as to remember the places, as the camera does not have GPS support. Very quickly, I realized that renaming each photo was not only a pain, but it also ended up ruining the sequence of the shots.
By renaming photos, some photos that were taken in the evening, ended up being placed before photos that were taken in the morning of a particular outing. As expected, I quickly gave up renaming photos. I retained the numbering scheme of the digital camera.
Recently, I came across the BulkRename utility. Using this utility, I was able to rename photos using the date when they were snapped, as this information is stored in the file. Though I was not able to rename the files to their original numbering, I was at least able to arrange them in the proper order.