Whilst I'm still learning emacs and gnus I'm constantly adding code to my
"setup-testbed.el" file, and then finding later that it doesn't do what its
expected to do, or I don't like the outcome, so I then comment it
out. Currently, I'm doing it laboriously by hand, but is it possible to
highlight it and then with one key-press insert ";" in front of each and every
line of the code please?

I haven't seen this ability anywhere, but being able to do it would make
things a whole lot easier for me, so, can it be done please folks?

Sharon.
-- 
A taste of linux = http://www.sharons.org.uk
my git repo = https://bitbucket.org/boudiccas/dots
TGmeds = http://www.tgmeds.org.uk
Debian testing, Fluxbox 1.3.5, emacs 24.4.50.15