Hi
I know this has been asked in the past, but I can't find a "Cast In Stone" answer here or in other places:
In My Keychain, I have a lot of certificates. Some are for places I never went to (examples: Go Daddy, Taiwan Post, American Online, Equifax Global Business), some are expired & some are marked as not being trusted.

Is it safe to ignore these? If not, should I delete them? (Which leads to the question"How?")

I would not mind if I had to re-build the whole thing form scratch, just as if this was a brand new blank hard disk with a clean OS install. Is is possible to delete the whole list? How is that done?

Thanks for the advice! It is appreciated.
Paul