1. Go to System-> Administration-> Users and Groups. Click on the user account to be deleted, then unlock it if necessary providing the administrator password. But in this case, the user's home folder still exists, as it was in my case. To get rid of this, you can follow the second method which is more reliable.
2. Open a terminal and type:
varsha@varsha-laptop:~$ sudo userdel -f username
3. Then to remove the home folder, type:
varsha@varsha-laptop:~$ sudo rm -r /home/
Check whether the user's folder is gone. It must have.