Here are the programs that I use:
Metapad - Notepad replacement. I have removed notepad from all my computers and use this now.
Source Edit - Free multi language editor. Also has free Hex editor. This program allows you to change text in all the files in a folder. I like it to change all the True to true and False to false in my UI directory with one command.
XML Spy - If you can afford it. I love this one because it has a nice grid view that allows me to edit whole blocks of code easily.