This is a difficult and fascinating question.

I have a few significant black holes in my memory from childhood where traumatic moments are missing. Some of these have resurfaced in later years (one at 21, and another more recently at 39). There are still gaps. I am curious at this phenomena of memory self-censorship.

On the other hand, I'm not sure I'd want any of my memories removed, even the horrible ones. They inform too much of my fiction writing, for one thing! I also believe they inform who I am now. But I can certainly see why some people would think differently. :)