glutKeyboard function.

I want to pause an animation that is on going and take screen grabs.

Can i use glutkeyboard()to do this.

Ideally, as one of the switch cases i would just cin>> another char which would resume the animation.
I have already used glut keyboard to adjust some data within the animation.

Yes, you can use GLUT for the keyboard input. The cin idea is bad and probably a result of inexperience.
Just save the screen and then resume the message loop.