Bad starter solenoid or starter relay. By jumping across the 2 bolts/wires on your starter as you described, you are bypassing the solenoid. I am leaning towards solenoid because I think if the relay is out your fuel pump wouldn't work. Check voltage at the same place where you jumped across the starter while you turn the key to start it. i am betting you will read zero.
edit: I didn't read the whole thread. Now i see the post above me says the same thing.