My first one was a pretty simple "job like" interview, asked the basic questions that most employers would ask.
My 2nd interview was more of an interview that related to why I wanted to join the Army, what can i provide to the Army, what I knew about the training, and the duration of each section (bmq, sq, moc) etc. etc.
I would highly recommend you fill the entire "Prepare for your interview" sheet, and bring er' on in with you, I even used mine a couple times to check over on some of the questions where I was about to go ....ugh...ugh! Really helped out alot.
As for the DEO interviews, I'm not sure if there's a difference? could be? maybe not? perhaps someone on here will give ya a better answer then i can heh.
Take it easy and best of luck!
Mike F.