A the top level, with 3 items showing on the menu, move down so that the second or third item is highlighted. Then use the joystick to go right, to the last set of items at that level. If there is only one item on that final page, and you have not moved back up within the page, you can click to start the game thinking that the item is selected, when in fact it is an empty slot that is selected and starting it crashes the vectrex.
A the top level, with 3 items showing on the menu, move down so that the second or third item is highlighted. Then use the joystick to go right, to the last set of items at that level. If there is only one item on that final page, and you have not moved back up within the page, you can click to start the game thinking that the item is selected, when in fact it is an empty slot that is selected and starting it crashes the vectrex.