Yeah, Fla is one of the few states that routinely does discovery depositions in criminal cases. If you can, meet with the prosecutor for a few minutes before it starts so s/he can prep you.
And yes, try to answer only the question asked, if you don't understand it ask for the question to be re-worded. If the question is objectionable, the prosecutor will object. Just be as honest and to the point as you can, and everything will be fine.
If it's any comfort, sometimes a good deposition can go a long way toward convincing the defendant to plead guilty rather than go to trial, so you never know--this may spare you more hassle down the road. No guarantees, of course, but it's been known to happen.