Under VISTA Command prompt:
Click on the System Icon
Select Defaults from the Menu
On the Options tab in the Options group I have
"Quick Edit Mode", "Insert Mode", and "Auto Complete" selected
I think that "Quick Edit Mode" is what makes it work.
To paste whatever is in the Clipboard at the insertion point: Right Click.
To copy from the Command Window
Select by holding down the left mouse button and dragging the pointer across what you want to copy
Once selected, right click
To paste at the insertion point, right click again.