Yes you can use the 3 monitors using your pc and your laptop. But you will have to be changing the connections physically each time.
Why would you have to change the connection each time when there are two inputs on the DTH2G?
I have two desktops and would like to use both with the DTH2G, my monitors have a source button to switch between input devices. My DTH2G and two new monitors are being shipped to me right now. I think it should work ok to use the analog input on the DTH2G for my 2nd desktop.
I was just curious if switching between two desktops would run ok or would it not work, also one computer is XP and the other is Vista.