VS 2010 Terms of Use

I made a terms of use form that has accept and decline buttons. It's the startup form, and I only want it to pop up the first time the user runs the app. If they press accept, I don't want it to pop up the second time or any other time they run the app, and if they press decline I have it set to exit the program. How would I go about this?

Also, when they press accept, the TOS is supposed to hide/exit and the main form is supposed to show.