Adobe Reader help (page chopping!)

I am using Adobe Reader to put together excel, word, and powerpoint files in order to make a single PDF. Some of the powerpoint files that have slides that are landscape and not portrait with graphics in them are 'chopped in half' and then continued on the next or next next slide. Is there any way that I can fix this?

How are you doing that exactly? Are you exporting those documents as PDF then combining them? Are you sure you're using Reader and not Acrobat?