> I've got it configured to use Notepad++. Free, and better than MS
> Notepad.

Same here.

I've got Universal Viewer configured under [Alt+V]iew, which can display most graphic formats (plus a whole lot of other file formats; it supports TotalCommander's Lister plugins).

Then, I've got [O]pen which relays it to Windows' extension-based association.

And for most other cases, I've created a batch script for the F9 Menu's top item, which runs its own commands based on the file's extension.

And finally, I've got a few launch commands tucked away in the e[X]ecute's history list (with associated shortcut key for easy access).

If I need to launch a file with some other program, I'll usually just copy its full path with [Ctrl+Insert],[F]ile, start the program through some other means (usually the Start Menu's search capabilities), and use its File Open dialog to open the file from there.