Re: taurus won't start
First thing I would check would be how tight the cables are on the battery posts. Mechanically, that is all that would have been touched. Getting to electrical, if the Alero gave off a pile of voltage when it started, it could have poked back into the Taurus, with possibly disastrous effect. The T has a KAM, or keep alive memory, in the ECM that is connected to the battery as long as the cables are connected. If you had a good surge, you could have eaten your computer.
Check for pulses at the plugs, check for pulses at the injectors. If you don't get any, and they would be the computer providing ground to the injectors, and ditto to the coil packs, your computer may be fried. You should also take a look at the PATS indicator on the dash if so equipped. The Passive AntiTheftSystem flashing light should stop flashing while/after you crank it. If it doesn't, then the key has not been recognized ..... coded again into the computer memory... whistle whistle whistle...