If you want to make a presentation that will surely leave a lasting impact, try Prezi(http://prezi.com).
For sample see the following link;
http://prezi.com/m-o5zmzgylzr/selling-saas-in-the-enterprise/
by
Gavin Sequeira , Executive Assistant to Chairman / Data Analyst , Binatone Lifestyle Pvt. Ltd.
MS Powerpoint is the best, but limited unlike MS Excel, wherein you can make auto updating dashboards. Personally, I prefer creating dashboards in excel which can be password protected so that formulae, vba etc cannot be modified unless required.
