1. Your screen resolution changed back to the 800 X 600 which would give your massive icons.
Go to System Preferences > Displays and change it back to "Best...."
2. You turned on Universal Access (Accessibility) accidentally.
Go to System Preferences > Accessibility and check that there are no check marks in the "Use keyboard shortcuts to zoom" section. (other than Smooth images)
Let us know how you get on
P
Not sure what I did but everything on my desktop suddenly is supersize, the icons on my desktop are big as well. I lost the image as a screen saver display. My desktop icons are not as the were and can not be rearranged. I have an IMac with 10.5.8. I have tried everything including a restart but did not help. Any suggestions ?? Bill

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