Reinstalling OS X 10.6 without losing any data My MacBook Pro 13' (mid 2009) won't boot. It doesn't get past the initial grey boot up-screen - and nothing I've tried seems to help that. The only way to get the computer started up is via the installation disc. And through that I've been able to verify that the Hard drive is not corrupt and still functional. But unfortunately I only have access to terminal there - and me being a terminal newbie -I have not been able to send the most critical of my files to another computer. 

This would have been desirable as I plan to reinstall the OS to (hopefully) solve the problem. 

So my question is: will I be able to reinstall my computer without losing my files. And if not, what kind of files will I be losing?

Also, I've phrased my question to be about reinstalling the OS without losing important files - but of any of you have any other ideas or tips for solving the ubderlying problem (without reinstalling the OS or by backing up important files) I welcome that too!
I would strongly recommend against starting any recovery/reinstallation attempt without having a valid (and verified) backup available on another disk. As you are still able to boot the system with the Install DVD you can


use Disk Utility on the Install DVD to create a full backup copy of your internal disk to an external one
copy /Applications and /Users to an external drive (which should cover "all" critical data)


Then just proceed with an reinstallation attempt.