Hi Phoebe and Welcome to Apple Discussions...
You can reintall the Safari application from your Mac install disc(s) or you can download and install Safari 4.0.4 here.
http://support.apple.com/kb/DL877
One of the requirements for Safari 4.0.4 and running 10.4.11 is the 2009-002 Security Update. Open System Preferences/Software Updates - Installed Updates. If that security update is not listed there then go here; download and install it.
http://support.apple.com/downloads/SecurityUpdate_2009_002__Tiger_Intel
As for Bookmarks, if you can launch Safari as it is now, from the Safari Menu Bar click File/Export Bookmarks and save them to the Desktop. After you reinstall Safari go to the Menu Bar and click File/Import Bookmarks.
If your current version of Safari is just a performance issue and isn't crashing or freezing.. try maintenance instead of reinstalling Safari.
From the Safari Menu Bar, click Safari / Empty Cache. When you are done with that...
From the Safari Menu Bar, click Safari / Reset Safari. Select the top 5 buttons and click Reset.
Go here for trouble shooting 3rd party plugins or input managers which might be causing the problem.
http://support.apple.com/kb/TS1594
If Safari crashess, go to the Safari Menu Bar, click Safari/Preferences. Make note of all the preferences under each tab. Quit Safari. Now go to ~/Library/Preferences and move this file
com.apple.safari.plist to the Desktop. Relaunch Safari. If it's a successful launch, then that .plist file needs to be moved to the Trash.
Carolyn 🙂
Message was edited by: Carolyn Samit