Some real good ones in here, ones that i even forgot about since i got forced off Win7. Windows 10 really helped oppress my want to poweruse Windows, and not the way the way they wanted me to.
7zip hasn't been mentioned and is real handy.
MPC BE. Media player that just works.
There was a playlist creator that worked with MPC-HC, but forgot about it as haven't used it in ages.
dbpoweramp i used to use, but i just haven't bought many CDs in a while. Mp3tag was also handy.
Joy2key. Purchased also, and good keyboard emulator for gamepads. IIRC i played through Stalker with this without the need for the keyboard! 32 button configs...
Those PDF readers mentioned are good for creating notes on. But not needed it for ages. Same with ifranview and notepad++ sadly.
Amazing how poor in comparison the commercial software is compared to some smaller projects.