Stalling Out

Carbureted engines need some warmup time so the choke opens all the way, or it'll load up and die from WAY too much fuel till the choke opens all the way.
This could be verified if you see black smoke when you start it back up again.

I say this because you found out that a carbureted engine needs to have the choke set before starting, so I figured you must have only owned fuel injected cars before this.

In any case your issue's all sound like carb idle mixture and choke adjustments.