I had to pare down the original question. Some of them were awesome questions, so I suggest you repost them, one at a time. Zinn's quote is a compelling one. I think that you would have to make sure in any presentation that you focus on the idea that Zinn comes from a dialectical point of view that stresses repetition of the basic structure of materialism in retelling history. I do think that Zinn's point is that if the structure that enhances social inequality does not change, historical narratives repeat themselves. For example, consider the situation between the colonists and the British. The same manner in which the former oppressed the latter, the Americans from colonists end up oppressing women, poor people, people of color, and Native Americans because the socio- economic structure was not replaced. The same can be seen in the instance of Jacksonian Democracy. More poor, White men were included in the political process. While this inclusion was evident, the same replicative process of oppression was seen in the Trail of Tears and the continual disenfranchisement of women and people of color. In this, Zinn would argue that the oppressor is a victim of the economic configuration in which oppression and control are the elements that end up defining power. For this reason, the oppressor is also a victim, not knowing they are a victim.