George, use the
Alt+Print Screen combination and it will copy the active window to the clipboard. You then open a new document and then select
Edit/Paste or you press
Ctrl+V. The canvas will resize itself to the size of the window that you're pasting.
If you want more empty space around your pasted image, then you need to resize the canvas.
Go to
Image/Canvas Size.... When you look at the section called
Anchor, then you will notice a few arrows. These indicate the direction in which the canvas will be resized. If you want your pasted window in the upper left corner, then you have to click on the upper left square. Then you have to change the
Width and
Height of the canvas.
If you make a full screen copy using
Print Screen only and you want to remove the surrounding areas, then you have to use the
Marquee tool and select the area that you want to keep. Then select
Select/Invert which will reverse your selection. Then press the
Delete key to delete the surrounding area.
If you place every screen copy on a separate layer, you will be able to move them around using the
Move tool.
Let me know if you have any more questions