The first most disturbing event on Dark Shadows was when Vicki killed Noah Gifford,
[spoiler]
Right, Vicki should have let Noah live and and let him strangle Daniel to death and therefore let generations of Collins cease to exist.
I don't see Noah's death disturbing at all, it was a necessary evil for the survival of every single Collins yet to come.
Tripwire questions Barnabas wanting to help Chris Jennings, someone he barely knew...what's wrong with that? Chris was under a curse and Barnabas himself knew all too well what it was like living under a curse. He felt sympathy for Chris' plight. I admire Barnabas for this and wanting to help Chris.
As for disturbing moments, I concur that the murders of Dr. Woodard and Carl were very disturbing. Carl a bit more considering he was a blood relative of Barnabas'.
I mean, when Vicki shot Noah, it was to save Daniel's life...she had no choice. I believe and still do Barnabas could have found another, less harsh way to deal with Carl. [/spoiler]