To get a second display, you need to attach a separate monitor. A second laptop will not work in this situation.
Each laptop has a video output, but no video input. So there is no place to plug a video controller cable into a laptop PC.
To get a second display, you should get a second display monitor (flat panel recommended, but any should work), which should be less than $200 at a computer store, circuit city, etc., and connect it to the video output of your laptop, to get a second monitor.
You will need to go into Display / Settings and select the new monitor, and select “Extend Windows Desktop” to get the second monitor to operate. The attached “helpful” file shows the screens you may be using, depending on your version of Windows.