1) "Airport/Airplane mode" means all radios turned off, in this case Wifi and Bluetooth. Unfortunately, the Wifi switch doesn't work reliably, so you should use a widget (like Power Control) instead to turn them off. That's for the larger EE. The PE has no Wifi switch; instead you press and hold the Rotate switch and select "Airplane mode".

2) The SIM card does nothing. Period. A nice thought with the dream of having a 3G model that never materialized.