Nothing complex, like configuring drivers, just basic useful stuff. Ill start.
Windows Key+T or Ctrl+Alt+T brings up the terminal window. Anything you can do through the GUI you can do through the terminal window.
Linux is very file oriented - everything is a file, and not really hidden from you. The directory where all your files are stored is "home/[username]" where username is your login username without the brackets. You really don't need to worry about the other directories unless you are doing advanced stuff.
The "CTRL ALT DELETE -> end task" equivalent of Linux is a 2 step process. Open up a terminal, and type in
ps -C [program name]
where program name is the name of the program that is hanging. Like "ps -C Chrome". It will give you a PID number on the output. Next step is to type in
kill -9 [PID]
with the PID and that process will be killed.
If you ever fuck up to the point where your entire system hands, you can always restart the the actual GUI, which is the thing that is hanging. To do so, you can use another console that is not running the GUI. You can press CTRL+ALT+F1 to access it (CTRL+ALT+F7 brings you back to original GUI) , log in with your username and password, then type in
sudo service lightdm stop
sudo service lightdm start
this should work for Ubuntu and Mint. For sudo password, use your username password.