A family of Microsoft word processing software products for creating web, email, and print documents.
You will find a small free utility on my web site called PrintFolders http://www.gmayor.com/downloads.htm. This will print the contents of folders to a text file in a variety of layouts. You can open the resulting file in Word and add whatever descriptive information you require for each of the filenames, then save the resulting document in DropBox.