Merge the following .reg file into your system and Windows will present a new context menu choice entitled: "View with Notepad" when right-clicking any file.

REGEDIT4
<this line must be present and left blank in the .reg file>
[HKEY_CLASSES_ROOT\*\Shell]

[HKEY_CLASSES_ROOT\*\Shell\Notepad]
@="View with &Notepad"

[HKEY_CLASSES_ROOT\*\Shell\Notepad\Command]
@="notepad.exe %1"