Since the long ago days after the demise of Norton Commander I've been looking
for another good replacement for Windows Commander and Owl comes pretty close.
It's a little pricey and has a lot more features than I need but (so far)
they've never charged for an upgrade and it sure does a nice job.
Owl Commander using multiple panels (windows) with an easy to use interface
which you can start using right out of the box. Menus, toolbars and hotkeys are
fully configurable. It also has built in Zip file and ftp support so you can
access Zip files and ftp sites just as easy as you can any local folder plus you
can have several file management commands going on at the same time which is
especially good if you have a big copy.
A built in viewer allows you to view the contents of a file right from the
program with the built in search allows searches by filename but by file context
If you're as frustrated Explorer as I am you'll want to check this guy out.