This drove me up the wall for a few days because it would tell me that I can't delete this application because it is required by Mac OS X.
Open Finder
Browse to your "Applications" folder
Get Info on "iTunes" (or whatever application you are trying to delete)
Go to the Permissions
Unlock the padlock
Set Everyone to Read and Write
Attempt deletion again
I ran into this problem trying to downgrade from iTunes 10.4 to iTunes 10.3
Open Finder
Browse to your "Applications" folder
Get Info on "iTunes" (or whatever application you are trying to delete)
Go to the Permissions
Unlock the padlock
Set Everyone to Read and Write
Attempt deletion again
I ran into this problem trying to downgrade from iTunes 10.4 to iTunes 10.3