The purpose of the paper presentation is to give a brief review of the paper to help jog the class' memory, to give background and contextualization information about the paper, and to set the environment for consideration of the topics addressed in the paper. The goal is to synthesize the information in the paper, not to repeat it. To that end, you should prepare a limited number of slides about each paper and assume that your presentation should be 10 minutes or less in length. I would suggest preparing the following slides on a paper, with your goal being that each of these topics occupies at most one slide:
Presentation of a chapter introduction requires different criteria. In these presentations you should focus on the big picture: what is the whole, and how do the selected papers fit into it; and what insights and facts are brought up in the introduction that are not covered in the chapter/section's papers.
Paper presentations are evaluated on accuracy, insight, and appropriate use of time.