Well, if you want to see how last year's
Inventor Award-winning team did it, go to
their site which gives the specifics.
In any case, if you want good resolution for the design image, you should go the "save as bmp" route rather than do a screen capture. It will give you more uniform, and in most cases higher resolution, images. The exception (there's always an exception, isn't there?) would be if you are illustrating the use of Inventor or capturing a problem using Inventor, in which case by all means, do the screen shot.