This is a free program that I've been using for years. It will catalog and display all software, hardware, current updates and license keys for all software installed on the computer.
Check them out at: www (dot) belarc.com/free_download.html
(If i enter the actual URL, the link shows as 2 or 3 lines long)
Once you run the report, print it and you'll have a full hard-copy report of everything on that computer.