honestly, thats the best they can explain it in 5 minutes. i think it would be great to have seen a series of films where there were 2 distinct trilogies. the first being games 1-3 but the 2nd trilogy would have followed the ideas made from mk4 through deception. kinda like 1-3 would have been liu kang against shang tsung and shao kahn with many subplots. and 4-6 would have been the story of quan chi and the dragon king (in a nutshell). liu kangs cool but i wouldnt want to see him be the main guy for every film. him being in 4 would be cool but obviously at the beginning of 5 hes dead but then he comes back as a bad guy and raiden also turns. the beginning of the game deception makes a perfect cliffhanger ending for the 5th movie.
if you are looking for some cool videos to watch, on youtube check out the intro movies for deadly alliance, shaolin monks, deception and armageddon. pretty cool stuff that gives an idea as to how movies should look for these games