In the days of Windows 3.1, I used a hack to change the value ".txt" to ".ini" If I remember rightly, I just opened notepad.exe in Wordpad, searched for "txt" and replaced it with "ini" then saved it as noteini.exe - which was fine.
However, that no longer works for some unknown reason. Perhaps you need to use a hex editor to do it.
You could try one of the many notepad replacements like Note Tab Lite (1,796K) click here Powerful Notepad replacement with spell-check, autocorrect, etc. (Direct D/L)
I suspect though that, like me, you prefer the simplicity of Notepad, but just want a few changes.