Corrupt Library Files, Disk Util: No Valid Packages, apps, plug-in probs

Question

Darn, I could just kick myself. The current state of my computer is flashing me back to a nightmare from my pre-Mac days.
While backing up files to DVD I inadvertently/mistakenly/clumsily/stupidly (not sure) dragged what I thought was a copy of the Library folder I had created on my hd into Trash. When some of my apps stopped working and messages about missing internet plug-ins began to appear I realized I had screwed up. I ran Disk Utility a few times and either got the error message: "No Valid Packages" or a system hang. I attempted to repair the Library by moving files back to where I thought they should go and now have 2 Library files (syst and user) that have become a bit convoluted.
The good news is that I copied all of the files from both Libraries to my hd so I think I have everything saved. The bad news is that I don't know what goes where and I don't have a frame of reference, (ie the file structure) to work off of. For example, there is only one folder, (Library) inside the System folder and I can't remember if this is right or not. (System > Library > Automator, Caches, CFM Support etc.) My User Library looks intact but may have had some files shuffled around.
The way I see it, there are three alternatives or a combination thereof:
1) Ideally, I'd like to be able to get the files where they belong and return the file hierarchy to it's correct state.
2) Start more or less from scratch and re-install all of my effected apps, plug-ins, etc.
3) I read about an archive function that uses the OS installation disk to return files to their proper places. Can't remember the exact name and haven't been able to find the knowledge base article.
TXIA for any advice you might offer that will help get me out this predicament.
~ I.M. Stewpid
Message was edited by: Old-E
Message was edited by: Old-E
Message was edited by: Old-E

Answer 1

Copying Library files is problematic because of permissions issues that arise when you then try to copy them back.
The procedure you're referring to is called Archive and Install which will install a fresh copy of OS X and archive the old system into a Previous System Folder. See the following:
How to Perform an Archive and Install
An Archive and Install will NOT erase your hard drive, but you must have sufficient free space for a second OS X installation which could be from 3-9 GBs depending upon the version of OS X and selected installation options. The free space requirement is over and above normal free space requirements which should be at least 6-10 GBs. Read all the linked references carefully before proceeding.
1. Be sure to use Disk Utility first to repair the disk before performing the Archive and Install.
Repairing the Hard Drive and Permissions
Boot from your OS X Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Installer menu (Utilities menu for Tiger.) After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported, then quit DU and return to the installer.
2. Do not proceed with an Archive and Install if DU reports errors it cannot fix. In that case use Disk Warrior and/or TechTool Pro to repair the hard drive. If neither can repair the drive, then you will have to erase the drive and reinstall from scratch.
3. Boot from your OS X Installer disc. After the installer loads select your language and click on the Continue button. When you reach the screen to select a destination drive click once on the destination drive then click on the Option button. Select the Archive and Install option. You have an option to preserve users and network preferences. Only select this option if you are sure you have no corrupted files in your user accounts. Otherwise leave this option unchecked. Click on the OK button and continue with the OS X Installation.
4. Upon completion of the Archive and Install you will have a Previous System Folder in the root directory. You should retain the PSF until you are sure you do not need to manually transfer any items from the PSF to your newly installed system.
5. After moving any items you want to keep from the PSF you should delete it. You can back it up if you prefer, but you must delete it from the hard drive.
6. You can now download a Combo Updater directly from Apple's download site to update your new system to the desired version as well as install any security or other updates. You can also do this using Software Update.