I had two DUI's too, but on the first one I had a "Suspended Imposition of Sentence" contingent on the fact that I didn't get arrested for the next however many years. My second offense was more than 10 years after the first, so it was still considered a first offense. Of course, we have very strict abuse and lose laws here so they really threw the book at me. (Too bad it wasn't the Big Book 'cause I didn't get sober for another two and a half years!) Anyway--the point of all this is that I only have to list the last DUI because the earlier one is no longer on my record.
All that aside, honesty is most likely your best policy. It would be much worse to lie and get caught than tell the truth and maybe not get the job. The right job will take you BECAUSE you are honest.
Good luck!