If, where and how to talk about personal problems during master in PhD application I am applying to become a PhD student in some institutions. My master record isn't exactly perfect mainly because I didn't complete it in time: I should have completed it in two years but it took me far longer. 

Now, during the master I have had some serious healthy and personal issues that can partially justify not finishing in time: I had to stay several months in my hometown without the possibility to study or do anything university related because of a certain situation. Even when I came back to University it took me quite a bit of time to fully recover physically and mentally. 

I wish I could tell this in my application since it can be important to not put me at a strong disadvantage with respect to people that took one year less than me to get to this point.

Should I talk about this?

If yes, where and how? I was thinking about writing a few lines in the cover letter but I have no idea how detailed such things should be. From one side I wouldn't like to give detailed informations on my personal issues to random people and from another side I'd like to be clear on how affected I was by them. I'd also like to be extremely clear that this issues, in my opinion, don't completely justify my delay in finishing the study.

Maybe I should simply not worry about it and just apply and see what it comes out of it, but I'm not in a mood to waste chances right now.

Clarification: the question refers to the programs that require some sort of cover letter/personal statement, as far as regards the programs that don't require it, I can do nothing about them.
I suggest you say very little in your application materials. Nothing more than "My completion was delayed by medical/(or whatever) considerations, now resolved." 

Just that. If you get into a situation in which you need to say more, it will likely be with a small group and you can go into detail as you see best. 

They will have some valid concern that the old issues won't cause a problem in the future, so be prepared to address that. 

And who can say, even yourself, what contributed to the delay. Illness, family problems, lots of things can cause stress that reduce focus and make things harder. Don't make assumptions that you've done wrong, at least not in public.