7-zip is better, faster and has more options then winrar and CO with multi-window file commander unnecessary http://www.7-zip.org/
Cobian Backup is all you will ever need (Email: Thunderbird → copy the
profil folder Outlook-> copy all mails with folder structure)
The in my mind unbeatable tool is the TotalCommander. I have bought the license, but the shareware version is full functional and only reminds you at the start that you are only suppose to use it for 30 days. For students the license is very cheap and i could recommend to buy it. https://www.ghisler.com/index.htm
mucommander works on windows/linux/mac and can run from a usb stick only,
FTP and compression (rar,tar,zip,...) http://www.mucommander.com
in case more then 2 windows are needed a very small tool is Q-dir http://www.softwareok.com/?seite=Freeware/Q-Dir
quite usefull is also the freecommander. It works great under windows but maybe also under other platforms http://www.freecommander.com/index.htm
while the tools above allow a easy handling of files and folders they are
not so strong in finding folders or files that take up to much space.
Several programs presents a given drive or subfolder graphical mann.
"space eaters" are then easily identified.
This is a small tool for windows only: http://www.hdgraph.com/ or the tool "Scanner" from this page (my favorite) http://www.steffengerlach.de/freeware/
This is a java based crossplatform tool that found particulary usefull: http://www.jgoodies.com/freeware/jdiskreport/
With infra recorder you have a nice free burning program http://infrarecorder.org/
To mount a iso file there are many different programs try to mount them
directly in windows, this works in most new versions. Otherwise these
tools might help:
wind cd emulator (I think most versatile!!) http://wincdemu.sysprogs.org/
The whole file mounting can be done encrypted which might be handy from time to time
I found truecrypt uefull for this, which has now been replaced with Veracrypt (that can open also truecrypt achieves) both make one large containers, these are then handled as virtual drive and one can put files in it. This is not very practical for use with cloud services because then the whole package has to be synched. the software can be installed or used as stand alone program (exe file) that is kept with the container. The encryption is strong.
Veracrypt: https://www.veracrypt.fr/en/Downloads.html or https://sourceforge.net/projects/veracrypt/
For use with larger amounts of smaller files that are synchronized over any of the cloud services I would recommend to use a different tool. See Internet - network tools: Cryptomator :
Working with the windows system path is a pain. This windows patheditor
makes things much more convienient http://patheditor2.codeplex.com/
For most other works with windows a fitting tool can be found on the microsoft sites.
The Sysinternals suite contains a fundus of very powerfull tools that can
be downloaded as a package or separate:
I regularly use Autoruns: https://docs.microsoft.com/en-gb/sysinternals/downloads/autoruns
I daily use ProcessExplorer:https://docs.microsoft.com/en-gb/sysinternals/downloads/process-explorer
The best thing, they are for sure virus free and work well with windows