You can host videos on videopress using your wordpress.com account.
you then display them on your self hosted wordpress site using the plugin.
Within wordpress.com you can set them to show the share buttons or not.
When you have share buttons turned off the video is only available as flash. This is because the HTML video is easy to save. The streaming flash one not so much. I understand the thinking here, but really if a user wants that flash video it is still pretty easy to get.
I would prefer that the showing of the share buttons and the flash only video security decision were separated. I want my videos to work on iPads and iPhones so I need to make them available in those formats, I am willing to accept that some people may download them BUT I do not want to advertise with big buttons "saying please steal my video, here let me make it really easy for you!"
So please consider making "share video: buttons one check box
and flash only video another.