I would work to get as much as you can removed from the public records as I could.
Insanity is a question that can come up on things that require medical certification for fitness, like a pilots license. You may be found OK eventually, but only after spending a lot of money and enduring a lot of hastle.
Realize, that if you faint one time and proceeded to act on bad advice you may never drive again.
In the age of computers, as old records are harmonized into single shared databases that last forever, it can seem scary.
A lot of older records for minor stuff, once only on paper, simply got lost with time. I suspect not any more.
You can get an idea how your records look by paying for a background check. I know the Tennessee Bureau of Investigation will run one for $35, bucks. Also maybe a good idea if you are thinking of moving in with someone or marrying them. There are limits to what a google search reveals.
Also, maybe try applying for a handgun permit and see what obstacles they uncover.
Maybe try voluntering to be an aux or volunteer police officer in your community, that might generate feedback that helps you understand where you stand. Folks in the law enforcement trade may have connections that enable you to clean things up.
Also, if you are ever arrested again, I wouldn't rely on legal advice from the DA. Maybe find someone that knows criminal law and has only your best interests at heart.