The easiest way to get all the content from a PowerPoint presentation is to export it to .pdf or .rtf.
1. Press alt+f to get to the files menu and backstage view.
2. Press 'e' or arrow to "export".
3. Press tab. The first choice is to export to .pdf or .xps. Tab a second time and press enter to activate this, or
4. don't tab a second time and arrow down to other export choices.
5. if you want .rtf, choose "other" at the end of the export list, and .rtf will be there.
the awesome thing is that all the presentation text is available!