When you give a demo, do not feel obliged to cover every feature and suppress questions until you finish. Your audience comes to the demo with expectations and sometimes prior knowledge of your product, so listen to their feedback. Speed up or skip sections that they have already seen, and go to the areas that they care about the most.
Too often I feel like the presenter of a software demo thinks he is being paid on a per-feature basis, and most bring all of us in the audience along with him. Nothing good comes from this approach.
If we wanted to see an exhaustive list of features rather than participate in a conversation with a human being, we might be tempted to read the manual or watch a training video instead.
Consider what you would want to see if you were in the audience. Give people a chance to ask questions early to keep them engaged and allow you to tailor the presentation to their needs.