In my experience, the most important thing is to focus on what you want the attendees to walk away with. That drives the format and content of your presentation.
Don’t worry too much about peppy & interesting – make the presentation memorable because the attendees “get” what you’re saying. Everyone has a preferred learning method: auditory, visual, tactile, etc. Make sure that your examples use different methods to illustrate your points.
If there are presentations before/after yours, account for the potential lack of energy in the room.
Don’t fill the room with your words. Fill the room with stories that illustrate your key points. People remember stories. Find stories that are relevant, with details, and some surprises.
Tell people what you’re going to talk about. Talk about it. Tell them what you talked about.
To get group participation (especially from a tired/shy group), first ask a question that requires a hand-raise for a yes (“How many of you … “). Then ask for a yes/no answer from the group. Finally, ask an open-ended question.
Don’t use Powerpoint. If you do, use a huge font and a max of 3 bullet points per slide. You can always hand out summaries afterwards. You want people focused on you, not your slides/handouts.