Here is a simple pulley system (where we have to consider the moment of inertia of the pulley). You can set the mass values for the two hanging masses, as well as the pulley itself. (The radius of the pulley is 5 meters.) Note : If M1 <> M2, then the heavier mass will fall (and lighter rise) .. the distance of fall is 5 meters from that original position (and thus the other rises 5 meters from the original position). The final velocity of the hanging masses will be shown at the end of the animation. The linear acceleration of each mass is shown next to the mass, and the angular acceleration of the pulley (clockwise=positive) is shown near the pulley. 
