Yeah, just pop the spark plugs and pour some of that oil down into the cylinders, that should free it up. What happens when a car sits is that a tiny bit of rust forms around the piston rings and holds the piston in place. You need to get some penatrating lube (wd-40 or PB Blaster) and give it a good shot down into each of the cylinders and let it sit for a while, I would probably repeat that a few times. Then take a wrench and put it on the harmonic balancer and see if you can turn the engine over, if so, then it's free and you can then put the plugs back in and try to start it. This would also be a good time to check the plugs and wires since you said it was sitting for a while, if they're bad you should replace them.
[/gearhead speak]
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