Preventing from going full screen

whenever i view my animaion on my browsers, it plays to fit the screen. Can somebody help with an actionscrip that will keep it the size it is meant to be. And if the actionscript has to be added to the first frame…does that mean to every layers first frame(there are about 6 or 7 layers)…one more thing…with the animation already done, how can i insert a preloader all the way in the begining?

thanks for reading this =) (yeah first post)