In preparing a partition for cloning, I needed completely remove all pieces of Apple Remote Desktop 2.0. After a bit of poking around, I wrote the following script. Remember to turn OFF the Remote Desktop agent in sharing preferences before you start. This script needs you to enter the ADMIN user's password for the fifth operation. Also, I think this leaves the menu extra around ... doh!
## Remove old components
rm -rf "/Applications/Remote Desktop.app"
rm -rf "/System/Library/CoreServices/ARD Agent.app"
rm -rf "/System/Library/CoreServices/RemoteManagement"
rm -rf "/Library/Receipts/RemoteDesktop"*
## Remove preferences
rm -rf "/Users/[ADMIN USER NAME]/Library/Preferences/com.apple.RemoteDesktop.plist"
rm -rf "/Library/Preferences/com.apple.ARDAgent.plist"
rm -rf "/Library/Preferences/com.apple.RemoteDesktop.plist"
rm -rf "/Library/Preferences/com.apple.RemoteManagement.plist"
## Remove local database
rm -rf "/var/db/RemoteManagement"
I think the "kickstart" script that ships with ARD does pretty much the same thing, but I don't trust scripts I can't see.