Some of the advice people hand out so freely is alarming.
Yes USCBP will take a DUI charge very seriously, if they are aware of it. When you go to the US get used to the fact that IT IS NOT A JOKE. One DUI charge does not constitute moral turpitude, but two DUI charges does.
I've been pulled into 2ndary questioning certainly 10 times at JFK/Newark. I have one ancient (20 yrs ago) DUI from the US, so I cannot avoid it. It's not nice, and it's certainly not polite (lol).
p.s. do NOT call the embassy and ask for advice, unless you have already decided you're going to go and apply for a visa.