2004 Ford Freestar wont crank or start?

Just bought a 2004 Ford Freestar minivan. when I turn the key, it wont start, the dash lights work and the gauges looks like they are working but it wont crank or do anything. the odometer will only show - - - - - - - - but no numbers. It seems more of a security or a key problem than a starter problem. any ideas ?