Shortcuts for resizing movies
                                          

Dragging a movie’s Size Box allows you to 
show the movie at any size and shape.

To preserve the movie’s normal shape while 
you resize it:
 
Keep Movie Shape: Shift-Drag Size Box

You’ll find that movies may play slower
when you have resized them.  Sizes that are
even multiples of the movie’s normal size 
will play better.  You may choose to resize
to half, three-quarters, normal, or double size:

Find Best Sizes:   Option-Drag Size Box