You all were not precise about playing movies externaly. Personaly i would add that by playing movies externaly you will not recive sound, music quality as in the game , that is becouse music and some sounds files are stored in different files than bink movie files.
So you will recive movie files only with sound and without music and movies will sound differentlyt than in game..
shortly speaking you can convert to avi and play movies externaly but movies will not sound exatly as in the game