The workarount requires a retail install DVD of Snow Leopard OS X 10.6, and upgrade with that, then get the download to 10.6.8 from 'software update' run from the computer, to get the file from Apple online. Then check to be sure other updates are also downloaded as needed. This would include finding a version of flash player, check for browser updates; be sure to not have a pile of updates try to download at once. System parts are best if done first. Does not hurt to restart the computer after the installation of a few important items, & before continuing, run Disk Utility> 'repair disk permissions' on occasion.
The Snow Leopard DVD is under $20 at Apple online store. There is a link to see/order it; and an authorized reseller or Apple Store may also have a disc in stock, or they could be sold out. Online is most likely... http://store.apple.com/us/product/MC573Z/A/mac-os-x-106-snow-leopard
From that installed version of OS X, you can access the App store for other upgrades and different software. You may need to upgrade the RAM to a higher than original capacity, at least 2GB is fair for a start; more if you get a later OS X system and install that. There are different minimum specifications and you need to go beyond them for more than just the OS to function correctly. Also, a good amount of free-space in the HDD is best.
Good luck & happy computing! 🙂
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