Which is better knowing or not knowing?

We live in a society we want to know everything, we want to know when things happen and when something is wrong. Yet sometimes it may just be better not to know. I had this discussion with a friend this morning. 
Her family has a history of a type of cancer running in her family, every male on her fathers side has it and he doesn't want to get tested for it, she was upset. Honestly, is it better to know? Or is it better to not know and not worry about when it is going to kill you? He is older, so even if he knew there wouldn't be a wonderful survival rate.  
So the question arises do you want to know when you're going to die? Or do you want to go on with your life without the burdening of knowing and constantly counting down until you're too depressed to care?
We all want to know what is going on in the world around us, technology is wonderful enough to provide us with the means of staying up to date, for those of us who bother to follow the news. Yet the news is scary, it worries us. In particular I was in tears last night after reading about the second earthquake in Japan, worrying about a friend. Then it changed to just being scared and worried about whats happening around the world in general.
Sometimes we all need a friend, and a hug.  

And for those wondering, I did hear from this friend, he's fine :).  

The news scares me.

'2 killed as big aftershock rattles disaster-weary Japan' on Fluent News. Here is the link: http://fluentnews.com/s/26639863

The news scares the shit out of me sometimes. Schools are shutting down in South Korea because of radiation fears, and yet another "aftershock" earthquake.. which would have been at about 10:30 ( EST ) this morning it was 11:30 last night there, I am slightly relieved only two people got killed. Yet I feel bad for thinking that.  Things seem to hit closer and closer to home.
I love being up to date, yet I hate with all my heart reading the news sometimes. Its depressing and it is scary as hell.

This carries a very common theme to yesterdays,
... rejoice for the people who walked from the rubble and pray for those who don't know...

I'm going to bed with tears in my eyes, for those who fight for their lives, whether it is to live through every day or whether they are trying to help someone else do the same.  I wish the best for all of the world. I worry for those who are close to me, and I have sympathy for those I have never met.
Our worlds in need of some hope, and if your more religious than I maybe a whole lot of prayers.
Some days I feel I need to pray and I'm not even religious. Tonights one of those days.