Hi.The genre of music that Depeche Mode has often been classified is as Electro-pop. That’s the reference that most often music critics and such associate with them. I’m fairly certain on that.
I've been listening to Depeche Mode since I was a wee 7 year old. I love their old stuff. Sarah, consider yourself very lucky to have got that CD as a gift. I bought the 'Ultra' album but didn't listen to it much. Barrel of a gun was the best song from it I think. The guy has an amazing voice - it's so unique.
their earlier stuff was great but later some how they last that touch. I would say they were the leading band when it came to inovative blend of music yrs back just like pet shop boyz. on their way down drug abuse did help them quite a lot.
i think when they started off they were categorized as 'alternative', as there music became mainstream, they moved into the 'pop' genre, but still not quite 'pop'.
I think there a mixture, alternative-electronica-pop....but some of their songs are even acoustic, they have a version of personal jesus you can download that sounds country...