So you have (1) already successfully entered the USA on an ESTA and (2) had no brushes with the law since then. It is therefore likely that you would have no problems getting in on an ESTA in future (regardless of legalities), ticking NO to each question.
The US authorities have no access to the PNC. They can only access data on a specific person by individual request, for which they would need reasonable grounds i.e. specific suspicion (making a random check is not reasonable grounds). They would then have to contact the UK authorities there and then, providing their reason for wanting access to your data. I.e. extremely unlikely that they would do this unless they saw a specific serious threat.
Applying for a visa is the correct legal thing to do, but for most people with any criminal record they will arbitrarily decline entry. Seems much safer for you to go on an ESTA. You are already in their system and marked as good to enter.
As you will no doubt see from your online research, people with far more serious criminal records than you have got in on an ESTA no problem. The wording of the question about moral turpitude has now changed to being about causing harm to someone else.
If you are worried you can fly from Ireland, where they have US pre-screening at both Dublin and Shannon airports. This means the US border control takes place at the departure airport. Then, when you arrive in the US, your flight is treated like a domestic flight, so there is no border control. That way, in the extremely unlikely event that you are barred entry, you only have a return flight from Ireland to worry about, rather than a same-day transatlantic flight at your own expense.