Powerpoint to HTML:
File Save as.... Web page or HTML.
Then FTP this page and the folder it needs to the website. Link to it. Clean and easy.
You can check options for different effects.
You can show the notes on the left side of the screen, slideshow on right.
You can turn off the notes
You can publish as archive pages, etc...
If you have the slideshow set to automatically flip every x seconds, the resulting slideshow (web pages) will do the same. Nothing special required by your browser.