Appearance Settings
No changes from OS X.4 to OS X.5.

Desktop Settings
There are new images for the Desktop. They are in Nature with Aurora, Earth, Earth Horizon, Golden Palace, Rock garden, Rocks and Zebra and in Plants with Bamboo Grove, Grass Blades, Lavender, Leaves and Lotus.
With the release of the X.5.2 update, you can also now turn off the Translucent Menu Bar. The readability of the menu bar can often depend on your choice of desktop picture.

Screen Saver Settings
New screen savers have been added: Arabesque, Shell and Word of the Day. You can also now turn on an option to "Show with clock" so that the time shows on the screen while the screensaver is playing.
Pictures from .Mac and RSS have now been added along with new display styles for pictures. You can set your screen saver to show pictures as a slideshow, a collage or as a Mosaic.
Recommended settings: Set screen saver to 15 minutes. This time is based on the Portable Device Security Standard that has been set into place by ITCS Security.

Dock Settings
These have not changed from OS X.4 to OS X.5.
Recommended settings: Turn off "Animate opening applications".

Expose Settings
Just a minor change in the the preference pane itself in OS X.4 from OS X.5
Recommended settings: Set one of the hot corners to "Start Screen Saver". This allows you to quickly turn on a screen saver to protect someone from seeing sensitive data.

Spaces Settings
This is new to Mac Users. You can have up to 16 different working spaces. It helps reduce clutter, letting you organize your windows and applications in specific work areas.
For a brief tutorial on how to use spaces, go to Apple's 101 page.
Recommended settings: Leave off until you're ready to use them.

Language Settings
These have not changed from OS X.4 to OS X.5.
Recommended settings: Leave to default unless you use another language as a primary language.

Formats
These have not changed from OS X.4 to OS X.5.
Recommended settings: Click on the customize button in the Dates section and change the year from 2-digit to 4-digit.

Input Menu
No changes from OS X.4.
Recommended settings: Leave to default unless there's another need.

Security Settings>General Tab
In OS X.4, there was only one pane in Security preferences. There are now three: General, FileVault and Firewall.
Turn on the following:

• Require password to wake this computer from sleep or screen saver.
• Disable automatic login.
• Use secure virtual memory.
• Disable remote control infrared receiver.

FileVault Settings
A carryover from OS X.4, this pane lets you encrypt your home folder. Use this with caution. If you forget your master password, the data is NOT recoverable. Here is the instruction page from Apple

Firewall Settings
Recommended settings: Select "Set access for specific services and applications". This will add services as needed. You will be informed by a pop-window if you want to give a particular service permission to access the internet.

Spotlight>Search Result Settings
Another carryover from OS X.4
Recommended settings: Leave everything on unless you know you absolutely don't use that particular category. This will trim down and speed up the Spotlight search results but with faster machines being released this isn't as necessary as it once was.

Spotlight>Privacy Settings
Also a carryover from OS X.4. Leave it empty except for the following situations:

• You see a delay while typing in the Entourage message window. Add the Office 2004/2008 Identities folder to the list.
• You have an external hard drive or thumb drive that you don't need to search. Add its entire drive to the list.