If it is a windows use the Ctrl, Alt, and delete keys at the same time. It will bring up program manager with a menu that will have several items on it. You can "unfreeze" it by ending a program or you can shut it down. If it is Apple go up to your Apple Icon at the top of your screen and highlight "shut down."
delete Windows Vista :D
Turn unit off
TF2 stops responding? sounds like a corrupt file, do you have non default skins or sounds installed. try re-installling steam
Restart or replace it
You need to scan your computer for spyware .
bromine
you must open the single player commands folder and open the game from there and it should work
the fan has stopped completely and the laptop should be serviced before there is heat damage
there could be two reason 1) Driver issue 2) hardware fault
The process is called habituation. It involves the decrease in response to a repeated or prolonged stimulus, where the organism learns to ignore or adapt to the stimulus over time.
Your speaker could have blown.
The Microsoft website has an extensive troubleshooting section which guides people through what to do if Internet Explorer stops responding. Some of the specific steps are pertinent only to a particular version of Internet Explorer.