It's odd; you'd think having a good default editor would be commonplace these days, but it's not. I've tried Vim for Windows and Scite in the past, but always ended up having issues with tab indents and formatting when working from my svn repository.
I found PSPad the other day and have enjoyed it so far. I used jEdit before that but found it a little slow, especially since I usually have 10 files open at once. PSPad is pretty solid and light on memory. One cool feature I've liked so far is that it can format a blob of XML into well-structured text (like when I paste the raw output from an Amazon ECS call into it).