Log in as root, assuming it is enabled. If it is not enabled you will need to do so. Off the top of my head, I can't remeber how to do so, I think it is in the NetInfo Utility, located in your utilities file.
If root is enable, you can drag and drop the folder into the trash, if you logged in using root. If you are using another user account, and do not want to log out, you can remove the folder and its contents using the terminal using the "sudo" or "su root" command.
From the command line type the following:
sudo rm -R /location of the folder/ (ie /Applications/app name or folder)
the terminal will ask for a password, type the root password
then go to the /Applications/ folder and type ls -a to see if the folder or app is gone. Or open the finder to see if the folder is gone.
Be very careful when you are logged in as root, as you can screw up your system unrepairably if you delete or edit the wrong files. Chances are if you are logged in as an administrator and it says you don't have privs to delete something, you might not want to be deleting it.