I was arrested for DUI about 7 years ago, but later the case was dismissed. The arrest still shows up on my FBI file, so it will be something that is uncovered during a background. I don't have to admit to any convictions or driver/pilot license issues, but when they ask if there is anything else that I would like to add, I bring it up then. It will be found during a background, and I'm not the type to cover it up anyway.
Honesty is the best policy. If the first airline I tell chooses not to hire me for it, I will continue to apply until one does. I'll fly boxes in lower Alabama if necessary.....