|re: My iMac (OSX 10.8.4) won't open Word (or a dozen of my other programs)|
You have a dozen apps that all give you a PowerPoint related error?
If that's true, then it sounds like you have a file association problem and your Mac thinks that all of the apps are PowerPoint files.
I'm not sure how you set file associations on a Mac, but I imagine it's something that you can find via Google.
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