Busted mac - how to retrive and save my data?

Question

Hi Hope someone can help -
My Mac has gone belly up recently. It starts up in the grey screen with an apple logo and a spinning disc before moving onto a blue screen (with occasional spinning wheel). I can move the mouse cursor in the blue screen.
Note - There is only 7gb of free space left on the hard drive.
I’ve tried many different options to get back into the mac including –
1. Trying to boot into safe mode – fails to do so.
2. Tried holding down the S key while booting up – no joy here either.
3. Holding down cmd-S to get into the UNIX command line – this was successful and I can see all my files and directories.
4. Cmd-C and running from the original OS-X install disc. From here I was able to run the disc utility but it reported no problems with the hard disc. I can also see the various files and directories from here. But I cannot see any way to copy/save my data using this option.
It’s been reported elsewhere that the above problem might be caused by the logic board failing, so re-installing the OS may be pointless, correct? And anyway a full re-install will wipe all my data. So at this point it looks like saving my mac might be a wasted effort, so my main emphasis is now on retrieving my data.
Perhaps someone might be able to help with the following (I’m fairly comfortable with using UNIX, but not an expert).
1. Could I copy the necessary files onto an external hard disc using Unix CP command if I simply attached another external hard disc to the mac?
2. Or could I simply cp my files to an external DVD re-writer drive from the UNIX command line? If so what would be the command to do so?
3. Any other options/suggestions?

Answer 1

Hi, I hope we can help as well.
Okay so your first concern is your data. Go and purchase an external hard drive that is at least twice as big as you think you will need. We'll use it to 1) Create a boot disk and 2) Put any data you can save in a safe place. After we are done, you'll use this external hard drive for backing up your data on a regular basis, so you won't need to worry about this nearly as much again. If you really want to be safe, get two external drives and back up your backup.
Boot the iMac from its install DVD. Use *Disk Utility* to format the external drive. Install the OS on it. Restart, booting from the system on the external drive. Copy your data from the internal hard drive to the external. You can use the *Migration Assistant* (in /Applications/Utilities) the UNIX cp command, a program called Carbon Copy Cloner, or any of several other methods. At this point you can also use the Finder to make a copy of critical files to DVD(s).
Once you have your data safe, shut down the iMac and disconnect the external hard drive. Reboot starting from the install disk again. Use the installer to do an *Archive and Install* of the operating system, preserving user and network settings. See [this article|http://support.apple.com/kb/HT1710] for further information about A and I.
If the Archive and Install works, you should be able to restart the computer and have it be working again. Reconnect your external hard drive and use it with [Time Machine|http://www.apple.com/support/leopard/timemachine> to maintain current backups for the future.
If all of the above fail, let us know, we'll keep working with you.
Best of luck.