Recording a simple gameplay

Hello, I need to record as simple as the gameplay screen. I want to click record and play the game and when i click “stop”, i need to have an “avi” file. Do you know how can i make it? Neither “take recorder” nor “sequence recorder” is designed to make movies i thing. It comes too hard for me because i want a simple screen recorder very simple. Please help me, thank you.

OMG! I thing i am over-worked. I searched the solution inside the engine but yes, windows+G ! i only need windows+G. thank you both the answer and make me realise that i need a break!

Windows? Have you tried just holding the windows key a pressing G?