Behind the scenes of Windows there is a place known as the Registry. For most user this is a dark place where people should not go. If you mess up in there you are likely to corrupt your whole operating system so it's best to not mess with it at all.
For the more advanced user that understands the dangers of the Registry it can be a place to pull out more functionality from Windows and at times clean it up to make sure it's working ok. As you learn more about how Microsoft makes it's software work you'll understand exactly what the Registry is doing and what it can do for you.
One of the tricks is to add "open with notepad" to the menu options when you right click on a file. This may seem something quite small to people who don't use it, but for people who need to open files quickly and edit them, especially developers this option can actually be quite invaluable.
Getting Open with Notepad into the Menu Options
The first thing to do is to start the Registry editor, this can be done by simply typing RegEdt32 into the search box on the start menu and press enter. This will load the editor for you, from there you open the "HKEY_CLASSES_ROOT" folder and then "*" until you find "shell". Right click on this folder and create a new entry called Open with Notepad. Then underneath that create a folder called "command".
In command double click on "(Default)" and enter "notepad.exe %1" for the value. This will work work straight away and you will find that all files can now be opened through notepad. There are many other "hacks" that can be done through the Registry but it's advisable to only do these types if you are sure what you are doing. Making changes to the Registry can make your computer unusable so always beware making any changes.