I don't want to seem like a dick and I am sorry for your loss, really, but med schools aren't going to just overlook a 25 MCAT score and a semester full of D's. After all, being a physician is emotionally demanding and medical school training is too. Med schools are interested in applicants that they believe are capable of handling this and you haven't exactly demonstrated this. Be honest, if you were a patient would you feel comfortable with a doctor who was on SSRI's and had bouts of depression that affected performance? Really think about this next question... do you really think you are capable of handling people's lives and dealing with the emotional traumas that come with severe illness and death?
I'm not saying you aren't capable, don't get me wrong. I just think it's important for you to really think about this.
"I took the MCAT a few weeks after my grandmas (she was basically my mother) death and a verbal reasoning passage made me emotional."
I know it isn't helpful, but in retrospect you probably shouldn't have submitted your MCAT for grading if you knew you got emotional during the verbal reasoning and your grandmother's death was still weighing heavily on you. Again, I don't mean to sound harsh but at this point I think an adcom would see this more as an "excuse" for a bad performance... and can you really blame them? It's not like you are the only person who has ever had to deal with a death of a loved one... there's never really a convenient time for anybody close to us to pass away.
If you are dead set on going to medical and becoming a doctor, I believe your best bet is to take some time off.. it sounds like you need it. I'd talk to whoever it is your need to talk to and try to get a leave of absence for the semester that way the grades don't count. Take some time off, get emotionally healthy, and really think things through. Once you feel stable and good, come back with a vengeance... seriously kick some ass in school, maybe retake some of those tough science classes but make sure you do well on them the 2nd time around. Definitely retake the MCAT again and get a good score... 25 is pretty low, im surprised you got an interview.
Personally, I wouldn't want to have that conversation with the dean talking about deferrment, depression, death, poor grades... I just don't think theres anyway to come out of that interview with a better chance of getting into that med school. I'd rather wait a year, and instead of spending an interview session defending yourself and explaining things away, you could have an interview talking about your strengths and how you needed some time off to deal with things, but you came back and excelled. Don't you think the 2nd interview sounds a lot better? And if you're planning to defer/take a year off anyway, then this doesn't really change your timeline at all... makes sense to apply as a stronger applicant.
That being said, you did get an interview for your top choice so there is still hope. I don't know what your GPA is but if it's really high, then 1 bad semester won't ruin your chances... and it's only October so you have time to improve some of those grades.
In the end, I really hope you make the right decision and that everything works out for you. I'm really sorry about your grandmother's passing and that it came at such an unfortunate time for you. I wish you the best of luck and hope my message didn't offend you!