My iMac late 2006 has a cracked screen so I have it plugged in to an external monitor. I opened it up and disconnected the inverter, webcam, and the display cable. This makes it display to my external monitor but it's having issues, the boot screen shows up to the external monitor but the screen then turns blue. Eventually I see my wallpaper and now I'm seeing the finder bar(didn't show up before) bu I can't click anything just, move around. My iMac internal screen isn't showing anything, is there any thing else I have to disconnect? Or something else I have to do?

Oh and I never saw the log in screen which makes think it's somehow still in extended display