Answered
How do I make Adobe Acrobat 9 the default for opening PDF files on Mac? And is there a way to make Reader 9 the default. I would like the instructions for going from one to the other. Sometimes make reader the default and sometimes making acrobat the default. running Mac OSX 10.4.11
There should be a section in the window that pops up titled "Open with"
In the section there is a drop down menu to let you choose the application and a button labeled change all. If you choose Acrobat 9 and click "Change All..." it should solve your problem.