OSX forgetfulness

I have noticed a rather peculiar problem with my otherwise stable 10.5.5 setup. Often when launching iTunes, I am presented with the license agreement screen as if it was the first run. Other times iPhoto will ask me if I want it to launch when I connect my digital camera (again as if it was the first run). Wifi networks that I ask the OS to remember are sometimes ignored, and Finder arrangement settings can be forgotten. I have been trying to pin down what the trigger is for this behavior but I can't seem to find a common thread. Has anyone else noticed this? Any ideas?

 

All of the Apple - MacOS applications which are available for free download
do their upgrades as a complete reinstall. This almost certainly hoses a
number of your Preference settings, including the Licence agreement.

Those applications that include network functionality will also grizzle,
each in their own way, if your network settings change since last time
you used the app. This includes iTunes, for the Music Shop, even if
you do not have an acct. Quicktime, even tho you have checked OFF
the "Show Content Guide at startup". iPhoto because it now has
a Flikr linkage, and the list grows day by day

I have wifi forget networks frequently on a real Mac, but I think in
my case it's because I often create ad hoc nets, or turn ON-OFF
internet sharing, enet to wifi. that seems to make it a feature, not a bug

Close all Finder windows.
Click on the Finder icon in the Dock to get a new window
Near center-left of the window toolbar is a gear-wheel icon,
click on this and select Show View Options.
Set to your liking, and close the window.
New Finder windows created from the Dock Finder icon will have these settings.
A Finder window created by Cmd-N will have the settings of the last window closed.
Go Figure ...