My IMAC runs OS 10.4.11. Can I upgrade to Snow Leopard with the $29 upgrade package or must I buy the more expensive "box set" that includes aps I will be unlikely to use?
Should you? Well, that's been debated endlessly. If you're interested, use the Search feature. You'll have a whole weekend's worth of reading material...
By the way, that is an answer to part one of your compound question. I'm assuming you're not an attorney. Lawyers never put "or" in a question.
At the end of the day, if you're going to go the $29 route, instead of the box set that Apple recommends (which by the way is a bargain at $126 Amazon.com: Mac Box Set 10.6.3: Software) then do a clean install!
I probably should have mentioned that, because even though I 'assume' that this is a given, there are endless posts here by people who have stuffed up and would have been fine if only they had time machine backups and/or clones.
My only other advice is to make sure that your applications are supported on Snow Leopard. If not you are going to have to upgrade them to newer versions or find an alternative. That goes the same for any of your hardware. IE printer, scanners etc.
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