Re: When I turn the key, I get nothing......
You probably have a pats issue. If I remember correctly, the pats system disables both the starter and the vehicles ignition if it doesn't recognize the key that is trying to start it. The Key has a chip in it (thus the over-sized plastic part) that sends a unique radio frequency identification code, which is read by a receiver in the ignition switch, this is why hardware store key copies won't work with your car.
If the key was ever dropped hard enough or submerged in water, it is possible that it has lost its RFID code and is no longer being recognized by your car, but there could also be an issue with the pats system in the car.
The fact that the security light stays lit for three seconds is a clue, but I don't know what it means, maybe someone who dose will chime in.
the reason that jumping the starter solenoid makes the starter turn but won't start the car is because you are directly powering the starter, but the pats system is still disabling the ignition.
Whatever the problem is, if its pats related you are probably going to need to take it to a dealership, sorry to say.
If you end up needing to take the car to the dealership, you may want to consider having them program a second key for you. Once you have two keys, you can program more yourself in the car.
1996 Mercury Grand Marquis GS ~89,000mi, Willow Green inside and out. It's very green.
1998 Chevrolet Malibu Base V6 187,000mi (sold)