Bought Used iMac - How to Erase Old Info and Install New?

Greetings,

What's the best way to erase all of his information and establish me as the administrator?

It depends on how clean you want the computer.
Quick and mostly clean:
1. Create a new user account for yourself and change it from "Standard" to "Administrator": http://docs.info.apple.com/article.html?path=Mac/10.6/en/8235.html
2. Log out of the current user: Apple Menu > Log out
3. Delete the original user account: http://docs.info.apple.com/article.html?path=Mac/10.6/en/8163.html
_This will delete the old user account and all it's contents leaving only your account. This leaves all the systemwide programs installed.

Long and very clean:

If you want EVERYTHING gone and just the factory programs / settings follow the steps in the help menu under "erase" using the 10.6 install disk.: http://docs.info.apple.com/article.html?path=Mac/10.6/en/27903.html

Once the erase and install is complete, update all your software by going to Apple Menu > Software update.

Once all the updates are complete, reinstall the bundled software (iPhoto, iWeb, iMovie, etc.) following this article: http://support.apple.com/kb/HT3415

One other question...I've never used Migration Assistant - can I use it to just transfer particular documents?

No. Migration assistant transfers all user files should you choose the option. However if you have an external drive or a firewire cable that will go between both computers, you can drag and drop whatever files you want to transfer (iPhoto Library, iTunes Library, etc.): http://support.apple.com/kb/HT1661

Hope that helps.

I strongly suggest that you erase the entire HD of the iMac & start fresh. This will remove any third party additions your friend might have installed or directory corruption that could compromise its operation, old logs, system settings, etc., as well as his user documents.

You can do the erase while started up from an OS installer disc with Disk Utility, launched from the "Utilities" menu prior to reinstalling the OS.

Note: If the included Snow Leopard disc is a retail one (which should be marked "Install DVD"), install Snow Leopard following the erase with this disc. If it is a special upgrade disc, for example one that says "CPU Drop-in DVD" instead of "Install DVD," it may require you to install Leopard from the grey system discs first.

It is simplest & easiest to use the Setup Assistant option to transfer at least system settings from your Mini on the first restart after the OS is installed. (This option of Setup Assistant is essentially the same thing as Migration Assistant, but SA runs automatically on the first restart & doesn't require setting up any user accounts prior to its use.) Like with Migration Assistant, you will be given the choice to migrate four categories of items from the Mini:

1. Network & Computer settings -- these are three basic subcategories of basic settings for time zone, network connection method, & machine settings. You can select them individually if you click the disclosure triangle next to the category name. I suggest selecting all of them, except machine if you intend to continue using the Mini as well as the iMac.

2. User Accounts -- you can select user accounts individually, & within each of them them you can exclude some folders at the root level of the account's home folder (but not individual folders within those folders). Again, you do this by clicking the disclosure triangles to reveal the options. The only folder in the account's root level home folder you cannot exclude is its ~/Library folder, which contains user preference & other files necessary to preserve the user's account info. I suggest migrating at least your primary user account from the Mini. Use your own discretion for which of its listed folders to migrate.

3. Applications -- this is all or nothing; however, Migration/Setup Assistant will not overwrite a newer version of an app already installed with an older one.

4. Other files & folders -- this applies to any files & folders at the root level of the drive you may have that are not in the system folders, Applications folder, or Users' folders.

This will give you a basic working iMac, set up very much like the Mini, but with a fresh-from-the-DVD OS. That OS will probably need some updates to get all its parts it to the current versions. If you were able to install Snow Leopard without first installing Leopard, you can run Software Update at this point to update everything. If Leopard is installed, at this point instead first upgrade that to Snow Leopard with the upgrade DVD, then optionally run Software Update. (Note: in this case, it is not necessary to update Leopard first.)

Finally, to reinstall any of the bundled software that came with the iMac that are not currently installed (like the iLife suite), look for an item on the grey system discs that says "Install bundled software" or something like that. Run that installer & select the items that you want or need. Follow this by running Software Update again to update them to the most current versions.

I know this sounds like a lot of work but it is easier than it sounds & you will end up with a Mac free of anything left over from your friend's use of it that could cause you problems in the future.

iLife should be on the Disk 1 but you need a program called Pacifist to extract it and install it onto your Mac. http://www.charlessoft.com/
Very simple.

Are you sure you are opening the "Install Bundled Software Only" installer icon on disc 1 & not the "Optional Installs" one? The organization of the system discs varies from model to model & year to year, but for my 2008 iMacs the Install Bundled Software Only" item is an alias & one of two items in the "Optional Installs" folder. When I launch the 'Bundled' item, the "Customize" button allows a choice of apps to install, including iWeb, iPhoto, & so on.