HT1338: OS X: Updating OS X and Mac App Store appsLearn about OS X: Updating OS X and Mac App Store apps
Currently Being ModeratedSep 30, 2012 10:19 AM (in response to mkersh)
Call the Apple online store, which in the US is 800-MY-APPLE, and order OS X 10.6 for $19.99. After installation, once you do Software Updates, you'll end up at 10.6.8, which will allow installation of iTunes 7 (if you have an iPhone 5) or give you access to the App store, if you want to upgrade to Mountain Lion.
You could upgrade to Lion instead of Mountain Lion, if you wanted, which is another call to the online Apple store to buy a download code.
If you upgrade to Lion or Mountain Lion, consider upgrading your memory to 4GB. 2GB is generally OK for 10.6 Snow Leopard.
Currently Being ModeratedApr 17, 2013 8:14 PM (in response to DavePT)
OS X 10.8 Mountain Lion is the current OS X and can be downloaded from the App store, which you can use after upgrading to OS X 10.6.
You may know that either Lion or Mountain Lion no longer run any PowerPC code. OS X 10.6 Snow Leopard is the last operating system that can run PowerPC code. People with Microsoft Office 2004 were surprised when it would no longer run under OS X 10.7 Lion. Newer versions of Office are OK. I have a dual boot iMac, with both OS X 10.6 Snow Leopard and OS X 10.7 Lion, as I have a few PowerPC programs I use now and then.
As mentioned above, consider upgrading your memory to 4GB for performance purposes if you upgrade.