I never knew it until last weekend, but you can actually rename a batch
of files directly in Windows.
Highlight all the files in the folder.
Put cursor arrow over the first filename, right click, then select
'Rename'. The first filename will go into rename node (like when you use
F2). Rename it, then hit return. All the others filenames will become
the same as the first, suffixed sequentially by (1), (2), (3) etc.
Any file can be the 'first file' (it need not be the one at the top),
but the others will be renumbered from the top.
Alternatively, after highlighting all the filenames, press F2. This will
put the top filename into rename mode, then continue as previously
described.