It used to be that when an engine stalled on an automatic transmission car, you would lose everything at that moment. Now, with the lock-up converters that is no longer true. The engine stalls, and you can no longer accelerate. However, you will still have power steering, brakes, and oil pressure because the transmission is still turning the engine crankshaft. Once you slow down to nearly a stop, it no longer can turn the engine, so you lose power steering and oil pressure. After that, you have one good press on the brakes and then the brake power assist is lost too.
This does not sound like an electrical system issue, because the OP doesn't mention any electrical loses, and does say that warning lights are on. I think that he is talking about a 2000 V8, but I do wish everyone would include such details in their posts.
It is interesting that the engine didn't restart while it was coasting, but did once the key was cycled off and then back on. This makes it sound like an engine electronics issue.