Having a light-weight Linux distro like Puppy Linux is always handy to have on hard disk. Of course, you can keep it as a CD or USB and boot it as and when required. But, I prefer the traditional way - have it in HDD when there is no scarcity of space.
First install Puppy after booting it from CD or USB. Installations are very easy to follow and self-explanatory. Choose the "Frugal" option if