Help speed up your old computers and get your feet wet with the most-used operating system in the world-LINUX! Ever wondered what Linux was, or how to use it? Well, now you can try on any computer, and see for yourself!
VitualBox:
https://www.virtualbox.org/wiki/Downloads
Puppy Linux ISO:
http://distro.ibiblio.org/puppylinux/puppy-slacko-6.3.0/64/
(Find the file called: slacko64-6.3.0.iso)
source