PDF2PPT-Free Software to Convert PDF to PPT
When you try to find a solution to Convert your PDF to PPT, you will find there are most share software, you have to pay for the conversion, but if you search it carefully, you will find two free software that you want.
If you have Adobe Acrobat(not Adobe Reader), I recommend you this one, it need Adobe Acrobat and Ms Powerpoint.
and If you do not have Adobe Acrobat, and you still want to do the conversion, I recommend you Acrobat Free Edtion PDF2PPT, it bases on PDF2PPM(part of xpdf).