Safari will not open, quit unexpectedly

Question

I cannot open Safari anymore. It will open to apple.com for about 1 second and then quit unexpectedly. Using Firefox now, but would like to know why safari is not working. I have already installed all of the available software updates.
Here is the error report:
Date/Time: 2008-08-22 21:21:57.734 -0400
OS Version: 10.4.11 (Build 8S2167)
Report Version: 4
Command: Safari
Path: /Applications/Safari.app/Contents/MacOS/Safari
Parent: WindowServer [68]
Version: 3.1.2 (4525.22)
Build Version: 6
Project Name: WebBrowser
Source Version: 45252200
PID: 844
Thread: Unknown
Link (dyld) error:
no suitable image found. Did find:
/usr/lib/libz.dylib: not a file
/usr/lib/libz.dylib: not a file /usr/lib/libz.dylib
Model: iMac4,1, BootROM IM41.0055.B08, 2 processors, Intel Core Duo, 2 GHz, 512 MB
Graphics: ATI Radeon X1600, ATY,RadeonX1600, PCIe, 128 MB
Memory Module: BANK 1/DIMM1, 512 MB, DDR2 SDRAM, 667 MHz
AirPort: spairportwireless_card_type_airportextreme (0x14E4, 0x89), Broadcom BCM43xx 1.0 (4.170.46.9)
Bluetooth: Version 1.9.5f4, 2 service, 1 devices, 1 incoming serial ports
Network Service: AirPort, AirPort, en1
Serial ATA Device: WDC WD2500JS-40NGB2, 232.89 GB
Parallel ATA Device: MATSHITADVD-R UJ-846, 3.96 GB
USB Device: Keyboard Hub, Apple, Inc., Up to 480 Mb/sec, 500 mA
USB Device: Apple Keyboard, Apple, Inc, Up to 1.5 Mb/sec, 100 mA
USB Device: Built-in iSight, Micron, Up to 480 Mb/sec, 500 mA
USB Device: Apple Optical USB Mouse, Primax Electronics, Up to 1.5 Mb/sec, 500 mA
USB Device: Bluetooth USB Host Controller, Apple, Inc., Up to 12 Mb/sec, 500 mA
USB Device: IR Receiver, Apple Computer, Inc., Up to 12 Mb/sec, 500 mA
Message was edited by: Sibster

Answer 1

Any other suggestions?
Just to supplement Barrry's valuable advice:
If your Safari won't open, one or more of the following procedures should fix it:
1. Go to Home/Library/Safari/ folder and remove the following two files:
• history.plist
• lastsession.plist
(Safari may not load properly If these two files are corrupted.)
2. Go to Home/Library/Caches/Metadata/Safari/ and remove the contents of that folder.
(These are just webhistory files and are not required for Safari to run. However, similar to preference files, problems can arise if they have become corrupt.)
3. Locate the cookies.plist file that's located in the Home/Library/Cookies/ folder and remove it.
(Again, faults in stored cookies may interfere with Safari's launch.)
4. Check whether any of your third-party internet plug-ins may be interfering with the launch of Safari by carefully moving them to the desktop (do NOT delete them at this stage). You can find these in two places:
Home/Library/Internet Plug-Ins/ folder, and Global plug-ins are located in the Macintosh HD/Library/Internet Plug-ins/ folder.
Restart Safari and place them back in the correct folders, one at a time, closing and re-opening Safari each time. If you discover that one of them was causing the problem with launching Safari, trash it and download and install a fresh copy.