Car won't start

I've a Chevy Cavalier 2000, which I use every now and then, and was parked for about 2 weeks without being cranked. After two weeks when I tried to crank it won't start. The batteries look fine, I changed spark plugs, but still no luck. When I turn the key it makes a rattling kind of noise from under the hood. Please help me with some good suggestions.

thanks