OK, I finally figured this out. My PowerPoint defaults to portrait view, so I just had to switch to landscape, and save the PPT in this format. Now everything is in landscape format, even the original portrait pages, but I don't care--it's much better than having everything in portrait format.
Windows 7 Pro, Wondershare PDF Editor.. I have a large PDF file (15.1 MB) with a mixture of landscape and portrait pages. Converting to PPT truncates all the landscape pages! This is incredibly frustrating. What can be done? The PDF file displays beautifully, and with the editor I can delete and insert pages wherever I want. But I need to get the file over to Power Point.