I use EditPlus, a very good editor for windows. I has about everything you need, is very flexible and can be easily customised.

Take a look at http://www.editplus.com

before that, I used the DOS EDIT editor. Know that you can use the version of EDIT, delivered with windows can edit multiple documents at the same time and that you can switch between them using the ALT-1 -> ALT-9 keys.

Kind regards,

Joachim.