Just wanted to add one more thing about this: in light of all the criticism Barnabas has gotten for wanting to change the past (and I admit a lot of times he, even unintentionally, winds up doing more harm and good), I think it's wonderful that he wanted to save Vicki from hanging as a witch. Some may feel that Julia would have been a better choice to help Vicki than Barnabas...I don't see how. As I said, Barnabas lived through those events, not Julia, therefore he was the more logical choice to go and help Vicki.
[spoiler] If only that dumb twist about Vicki getting killed by Jeb hadn't happened during the Leviathan storyline. [/spoiler]