What do people use to replace the old DOS Magellan/QDOS for viewing
and manipulating files?

The sorts of things I would like to do:

filter files by extension, name, size, last mod date, last access
date.

sort files by extension, name, size ...

select groups of files to copy, delete, move.

View file contents rapidly, ideally just down arrow with some sort of
resident viewer rather than waking up the app itself in most cases.

I'm using windows,but a Java app would be nice, especially one I can
tinker.