Those links have more info on Chrom plugins and how to enable or disable them.
From the first link:
By default, Chrome uses a built in viewer to open PDFs. If you've disabled the built-in PDF viewer, Chrome will use Adobe Acrobat or Adobe Reader to display PDFs. Follow the suggestions at the first link if you're having trouble viewing PDFs within Chrome, using Adobe Acrobat or Adobe Reader.
First check if the issue is specific to Chrome. Try opening PDFs in another browser on your computer, such as Firefox. If you experience similar problems viewing PDFs in another browser, the issue is likely not related to Chrome.
Thanks - I'd seen these. The trouble is that the Adobe Reader plugin doesn't appear in the plugins list, so the measures to activate it or deactivate the native Chrome PDF reader don't really help here. I suspect its just not supported - the system requirements for Mac don't list Chrome as an option, only Safari: http://www.adobe.com/uk/products/reader/tech-specs.html
As someone just switching from Windows to Mac, this is one of the disappointments.
"As someone just switching from Windows to Mac, this is one of the disappointments."
You'll find over time the advantages far outweigh the disappointments. I switched back before Intel processors, Software was much more limited, and things ran a lot slower on a 400mHz PPC processor, than they do on a Corei7.
I'm getting a new MacBook Pro next month and I'l be gald to be back on a Mac again. It's been three years since I lost my MBP 13".