Cheat Engine is an open source tool designed to help you with modifying single player games running under window so you can make games harder or easier to play depending on your preference (e.g: Find that 100hp is too easy, try playing a game with a max of 1 HP). Cheat engine also contains powerful and useful tools to help debugging games and even normal applications.
If you have forgotten your Windows Administrator password then by using guest account or any other limited account you can reset administrator password very easily. All you have to do is to create a file, paste the following script in it and set desired new password in it. Save that file in .vbs format. Run it, Administrator password will be changed.