With engine running I turn the key to turn on lights & the engine dies

Check the code first!!!

Usually when the engine dies and the key is still in the run position all the lights will come on. Do they stay on when you turn off the key?

I assume there's a problem with alternator. Check the grounding to engine, check continuity of a positive wire between alternator and battery. the energizing voltage should be checked as well. Might be the bad connection between battery and vehicle body grounding. Diesel cars are sensitive even in a little loss of connection and rust in the connection points.

The battery might be low but I doubt it is causing the "no idle" problem.
You should have an idle air control valve that the computer uses to adjust idle speed. That valve could be faulty or dirty.
Is the check engine light on when the engine is running ?

Well first it should only restart in park or nuetral, any check engine light on? May be fuel pump if not. Listen for pump running in fuel tank. Should run at key on for a few seconds. If check engine light on, it should be scanned for codes, possible crank sensor

If the gas in tank is that old you need to drain it. Once you have good new,clean fuel in tank. Turn key to run position,(do not energize starter just want red lights on dash to come on) listen for fuelpump whine. It will shut off. Turn key off.Turn key to run again, listen for fuelpump again. Turn off key again. Repeat this procedure total 5 times. On last time turn key to engage starter. It should build up enough pressure & fuel & start right up.

the 3 key turns dosent work on 2004 chryslers.i think 2000 or 2001 they removed that function from all chrysler/jeep/dodge/plymouth products

when key on and engine off, does the security light flash constantly? if so its shutting down the fuel pump, it starts momentarily due to the computer priming the engine with fuel. how to reset, turn key to run position, leave it on touch nothing, takes 10-12 minutes, start watching light around 10 minutes. it will stop flashing... turn key off, then back on and start this will reset the security system. they are sensitive on this platform car it will happen again. good luck!

Any chance your vehicles have a security/alarm system. Disconnecting battery on some, will arm it sometimes & not allow it to run. Using key to unlock door, on driver & passenger side have been known to work on some vehicles, but if not, a call to dealer should help.

You have a problem in the fuel pump relay circuit for sure then. I'm betting the relay, but it could be that dropping resistor.