Did you forget your system password
then try like this to start your system without giving password.
1.Start system whn it asks password tipe alt+ctrl+del two times it displays a box asking username & password .Then type username as administrator and leave password as blank and press enter .Now windows will start .Now goto control pannel/user accounts and delete your account
OR
2.Start system press F8 button after starting and select SAFE MODE and start windows,delete your account after that