Elliptical tool problem

[Meenie50]

I watched a tutorial on changing eye color. In the tutorial they showed you to use the elliptical tool to outline the iris of the eyes. He just dragged the elliptical tool and it fit the shape he was drawing around. It doesn't do that for me! Why?
When I try to do it, it moves around and doesn't come close to fitting the iris. 
I tried using the move tool to change the size but that does nothing. 
I read hold shift and drag... nope nothiing
Help??? <sigh>
(the tutorial I watched is here: 

  

[Gear maker]

The Elliptical Marquee tool only does circles/ellipse.  It doesn't use any smarts, so you have total control.  The narrator just has experience in picking his starting and ending places so it looks like it's doing it itself.  The shift key just keeps it round.  You can move it by grabbing in the middle and moving it, while still in the Elliptical Marquee tool.  You can hold down ctrl to add to it and opt to subtract.  But I know of no way once the mouse button is released to resize it.  Just start again.

[firstdefence]

Actually there is a way, you can use shapes or the pen tool to make the shape you want, edit it to your hearts content and the go to Select > Selection From Layer the advantage of this is you always have the shape to re-edit and make a selection again. There is also the option to make the selection and then delete the shape.