How much RAM on that PowerBook Pro?
How were the PDFs created?
You can check that out by opening the PDF in Acrobat and going to File>Properties
Go to the Description tab - and it's listed under Advanced
Produced with IText 2.0.2 (by Iowagie.com), PDF version 1.6 (Acrobat 7.x)
However, some of the pages place just fine, and some crash every time. Suspect there's corruption on the crashing pages.
Is there a way I could save the file in a different format or program and open that into Indesign?
Make sure you get the CS6 8.0.2 update released today. There were fixes for PDF issues, don't know if it's yours.