Can't open Finder, Trash, Chrome, and many other apps
Can't open Finder, Trash, App Store, Chrome and any other apps on Macbook. Clicking on the app icons from the dock or trying to open from Spotlight does nothing. The menu bar on top is viewable for more drop-down options but nothing happens when I click into it. I'm not sure how this happened. May have deleted some files I'm not supposed to? I was told the directory file is not being recognized, so it may be corrupted.
Got an error when I try to open Finder:
The application Finder can't be opened. -10810
Running on OS X (Snow Leopard). Tried to reinstall OS X but it keeps telling me "this item is temporarily unavailable."
Any ideas how I can reinstall OS X Snow Leopard when none of the apps are opening for me? Or does Mac have something similar to a PC restore where I can restore it to a previous time or condition? Hoping one of these will solve my problem.
I have a lot of important files on it so a factory reset and erasing everything is my last resort. I really hope it doesn't come to that.
Greatly appreciate it if anyone can help me!
MacBook Pro, Mac OS X (10.6.8), null