If you drain the oil out then everything inside the crankcase will rust and your oil pump will loose its prime.
You must either store it with a full tank of gas or bone dry.
Mike makes a good point about the coolant, change it before you go, dont use plain water as it will corrode everything and if ti gets cold enough it will freeze and crack your radiator.

 

Glad you caught the plain water thing. Just didn't want him throwing a lot of Dexcool in on a partially flushed system and letting it turn bad over 3 years. Also added the Water Wetter to help coat all the parts.