Well, normally, when you hook up an external monitor, it extends the desktop so the resolution of your 15" display will be 1440x900 and the 20" will be 1680x1050.
My plan is to just close the MacBook and use the wireless apple keyboard with wireless mighty mouse and have the macbook hooked up to the display. Would that work?
Yes, this is the way I am set up at home. If you have the new graphics update installed you need to start your macbook pro with the display attached, closing the lid immediately after pushing the start button. The unit will then recognize the display properly.
My plan is to just close the MacBook and use the wireless apple keyboard with wireless mighty mouse and have the macbook hooked up to the display. Would that work?
Also using my MBP this way. I haven't had any issues with the graphics update, though.
When taking the MBP with me, I unmount external drives and put it to sleep. Then, unplug the drives (USB/FW), then the display USB, then the monitor connector. Take the MBP to destination, wake, and use normally. When I return home, I plug the display connector in, then the rest of the USB/Firewire cables. It usually wakes when the display's USB is connected. The machine is closed, and the internal display is, as expected, off.