What exactly do you mean. Do you want to have a background and play the video in front or just play a video with a black border?
If it's the first you want to do, you can't. At least not until there is the option to place an avi inside a sprite (it's afeature that I have request and mnemonic has said that he might implement it). If it's the second you want then you can do it.
From the docs:
PlayVideo(Filename, Type, X, Y)
Filename: Filename of the AVI file to be played.
Type : Type of display, 0=at a given position, 1=stretched, 2=centered. Optional, default=1
X : X position on screen. Only used when Type is 0. Optional, default=0
Y : Y position on screen. Only used when Type is 0. Optional, default=0
Return value : If the method succeeds, the return value is true.
So, you have to put type=0 and then put the x & y values in whatever suits you (depends on the resolution of the game and the video)
