Video Popup window with a video player?

How can i do a popup window that has a video player, so that i can have the player click an icon and it plays a brief itroduction video. Dont know c# so if someone knows how to do this with playmaker/ngui it helps, but if someone can write me a ready to use script i can work with that too. Sorry for asking such a simple thing, but i could not find any help with this anywhere.