setting focus on control

how do you have the page set focus on a certain control on load..

also, how do you set which is the button that executes when the user presses "ENTER" ? (the equivalent of the Default = True property from VB6)

At the moment, I haev a form with 1 textbox and 1 button.. i want the form to load with focus on the textbox and when the user presses Enter, it should execute the button's click event..

thanks!