A couple of Questions about the FSCOMMAND!

So I hear this is the place for flash questions. I also heard this is where all the smart people are at! I hope so, cause I will have a ton of questions. Lets get started. I would like to know if the fscommand can launch a mpg? I am making a cd and want to load a mpg into the root directory and use an fs command on a button , to load the mpg so i dont get any loss in quality. I run it and the mpg dosent play. Is that cause fscommand wont let me? Ohh and by the way, feel free to explain to me the dynamic of the fscommand…i really dont know to much about it, so could someone help me? You guys are great, and i want to be someone replying to inncoent flashers like me some day! Thanks!