Living in the 12th century is an interesting idea. That may help us to understand peoples life in this century.
On the one hand, I'd like to live in the 12th century,because there's no computers,fresh air and it's easier to live there with knowledge that we have now.
On the other hand,I wouldn't like to live in this century,because there's no sanitation,and a lot of different diseases .
Anyway,it'll be interesting to live in this century,but only for a few days. Only to feel and see how people were living in the past.