Actually, you mentioned one of the first things I would do: change the fluids, oil and filter and the GAS. I'd drain the tank ( siphon if you need to) of anything left in it, and put fresh in. I'd put in a fresh fuel filter while you were at it.
Obviously, a new battery is in order.
Check the coolant level, if it's low top it up, but I wouldn't bother to change it untill the rig is running.
Check the airbox for critters, they love to nest in there after a long time.
Inspect the engine compartment carefully, looking and feeling for dried out or chewed threw wiring and hoses.
I'd pop the plugs during the oil change and turn the motor over by hand, using a 17mm socket and ratchet and cheater bar turning it over using the center crank pully bolt. This would assure everything is free before you tried to crank it.
I'm sure someone else may have other things to check, those are just off the top of my head.
One more thing, you might want to spray some penetrating fluid on any nuts, bolts or screws you intend to remove a day or so before you try and remove them, like the airbox screws, in the spark plug sockets, fuel filter clamp, even the oil pan drain plug.
Hope this helps! Have at it and good luck!
