my OS X 10.5.7 is really screwed up!!

im running 10.5.7 and when i open my "macintosh HD" i see all of this

Applications
bin
cores
Developer
efi
etc
Library
private
sbin
System
tmp
Users
usr
var
Volumes

i don't know what to do without KILLING my mac

thanks for helping
(whoever does ;D )

You are seeing all the normally hidden files. Whatever you do dont move or delete any of them.

Download MainMenu, MainMenu | Keep your Mac in shape

It will let you hide invisibles again, as well as being a great general maintenance app

I downloaded it but how do i make it make the unhidden files hidden??

Simple fix:

Open Terminal (/Applications/Utilities)

Type this exactly without quotes (Actually just copy and paste it):

"defaults write com.Apple.Finder AppleShowAllFiles NO"

Press return, then type "killall Finder"

Press return again and they should be hidden again.