Pause for timedelta?

Been doing alot of scripting on diffrent stuff, and alot of things tend to be dependant on using Time.deltatime to process there stuff, but now I am at a point I need a option to pause game time for some things, but when I just stop using the things that process the deltatime, the time still increases based on the amount of time the project is running if I am correct.
So if i wanted to pause the game, say if player opens a window like inventory or main menu/options menu or something, how could i prevent deltatime or what not from updating so time in a sence stands still while there are in that area then resume afterwords?

 

For everything that should be paused, continue using Time.deltaTime, and do Time.timeScale= 0;

For everything that should not, use Time.unscaledDeltaTime which is not affected by the timeScale value.

http://docs.unity3d.com/ScriptReference/Time-unscaledDeltaTime.html

 

@LightStriker
unscaledDeltaTime? O_O Is this new? I wish I have known this before..

 

It is... I think from 4.5, not sure the version that introduced it.