Div Toggle

Div Toggle

This is my first post so if its in the wrong spot I apologize.

What I am looking for..
I am trying to style up my simple contact form using jquery.  What I am trying to do is have one single text input that will be used for both 'email address' and 'message'.  So once the user enters their email address then hit's the enter key the box clears and the user then enters their message. 

I have only been messing with jquery for a few hours now so I don't know if its the best way to do it but I was looking at the toggle effect.  Is it possible to toggle between 2 divs? Example.. the user enters their email address then when they hit enter the div toggles to another div with the second input box asking for the message.

I did notice the 'toggle style' under the jquery demos which is kind of what I am attempting to do just it doesnt change the content just the style.  Sorry if this just sound's like a large ramble.

Anyway any help or suggestions would be highly appreciated. Thanks.