Delete /Library/Preferences ?

Question

One of my users has a couple of odd things going on.  One is applications complaining about weird keychains.  Adobe Reader was beefing about something like ~/Library/Preferences/Adobe/Acrobat/11.0/Security/somethingorother  On that same machine, I saw something unhappy about BuddySomethingOrOther keychain.  The other issue is login attempts that sit there with a spinning beach ball until the system is rebooted.
My initial thought was, "Delete all system preferences!"  But I couldn't find any mentions of doing that via Google, so I figured I'd check first :-)

Answer 1

Ah. Your initial post noted:
~/Library/Preferences/Adobe/Acrobat/
Since the tilde means the user account, I the presumed you meant any preferences related to that folder, not the root Library.
For the main /Library/Preferences folder, I wouldn't touch until I knew I had a way to easily fix it in case the Mac wouldn't boot to that partition after clearing it. It's easy enough. Just have any other partition with a bootable installation of OS X on it that has been tested to be sure you can indeed startup to it.
Then as before, move all preference files in the /Library/Preferences/ folder to a new folder. In this case, better to move them (or copy then delete the originals) to the other bootable drive so permission issues don't prevent you from getting at them when starting up to the other partition. Restart. Since they are preferences, and not critical system files, the Mac shouldn't have any trouble restarting. It should rebuild anything that's missing at default settings.
However, that's what the other bootable drive is for. It the Mac does balk at the removal of these preference files, then you restart and boot to the other partition. From there, copy the original preference files back into the /Library/Preferences/ folder of the drive you're testing.