Bad gas, water in fuel, Low fuel pump pressure, dirty air flow sensor screen, one or more engine sensors defective and/or out of normal reporting ranges, engine control computer defective. Low battery and alternator output. The "check engine light" should have come on to give you a hint.
When driving the IAC does not do anything because the car is not at an idle
a loose transmission or shifter rod might move the gears around a bit and make it stall
It could.
running out of gas? is it carburated?
yes a bad converter will make car stall
if you have a cracked distributor cap then water would get inside it and make your car stall.
Peeing off the side
A bad crank sensor will definitely cause the car to stall. Eventually the car will stop starting up again, or if it does, it will die down around ten minutes. A good thing to do if you're sure it's the crank sensor, replace it.
Remove the muffler
It might have run out of gas.
Front Wheel alignment
fuel filter