noob questions about how to update software

[vistadude]

How should one go about updating software in Mac OS X?

For example, I have old versions of opera and iTunes and want to download the new version. Do I first uninstall the existing apps by dragging the icon from the dock to the trashcan and then double click the new installer? What happens to the settings and other files left behind by the old installation?

Alternatively, can I simply double click the installer and will it overwrite the old version?

OR.... Do I drag the installer on top of the old icon in the dock?

I'm terribly confused as you can tell

 

[angelwatt]

iTunes is automatically updated via Software Update (under the Apple menu). Software like Opera are updated inside the app. If you choose to download a new version, you can simply do the normal install and it will replace the existing install. No uninstalling necessary unless the software says you need to. The dock icon is taken care of autmatically as well.