Depending on your climate, valves that are open can let mositure in and rust can develop on the cylinder walls.
My hack shade tree mechanic methods for firing up a engine that hasnt run in awhile are as follows:
#1: Dump a bunch of fresh gas in the tank
#2: Pull the plugs, clean 'em off.. and shoot some WD40 down the holes
#3: Drain the engine oil, and fill it up with fresh stuff.
#4: Take the fuel line off the carb as described in an earlier responce, make sure fuel is getting up to the carb.
#5: Hook the fuel line back up, squirt a little starting fluid or gas in the carb, and fire it up.
If it won't start.. check the usual suspects.. gunky rotor or cap, points, dry rotted plug wires, mouse eaten wires to the coil, that sort of thing.
