Users expect the submit and cancel buttons to be located at the bottom of a form. Moving the location of the Submit control is not recommended.

if (document.layers) {
   document.captureEvents(Event.KEYPRESS);
}

document.onkeypress = function (evt) {
   var keyCode = evt ? evt.which : event.keyCode;
   if (keyCode == 13) {
      SubmitView.doSubmit("Submit");
   } else { 
      return true;
   }
};