Puppy Linux Tahr 5.0.6 fits into 1G of disk space and runs well on only 500mb of RAM on an old XP box.
After playing with Puppy Linux, both the Slacko and Ubuntu 14.04 Trusty Tahr version, on CD, I decided to install Puppy Linux Tahr 6.0.5 as a dual boot alongside Win XP. The instructions online are not crystal clear to me, and left me somewhat puzzled, stomach ill at ease. Let me explain the process.
Puppy Linux can be used quite readily from your CD or USB stick. You need to boot up and then configure. I decided to dual boot install it on an old Win XP box, one with only 500mb ram.
Many days, I did struggle with this problem. My old 2010 HTC Google Nexus One simply would not connect to Ubuntu 14.04. A couple of weeks ago I gave up. Today, I had the brilliant idea to try connecting the Nexus One to Windows 7, and by a fluke of connecting to Win7, Ubuntu 14.04 also detected it. Why did this happen, I do not know, but I am thankful for these lucky flukes of the universe. Praise Zena Princess Warrior, for her good luck and intervention.