Hi Ted,
Some ideas:
1. Convert your original PPT's to PDF's and post those PDF's. Many people prefer to consume presentations via PDF so they can save the work locally and read offline, print and/or search the content vs being forced to page through an interactive web site. Count me as one of these ornery individuals.
2. Convert your original PPT's to PDF's, then use a utility or online service to slice your pages (slides) to a collection of standalone images that you present via s standard image carousel interface.
3. Convert your original PPT's to PDF's, then use an online PDF-to-PowerPoint converter to convert back PowerPoint?
Malcolm