You either open up notepad as administrator (C:/windows/notepad.exe), right click > Run as Administrator. Then File>Open and go all the way to the file location.
Or you turn off that damn protection, but as I'm not sure how on 7 or if you know how to at all I don't see that happening.
Of course, this is when you have those powers. I suggest you don't install your future games in Program Files.