I've been looking for a suitable distro to be install onto an old desktop/laptop. Started with DSL, Fluxbuntu, Xubuntu and UbuntuLite. Xubuntu is not suitable if you have ram less than 192Mb. As for DSL and Fluxbuntu, using Fluxbox as a window manager is sort of disadvantage for my targeted user. UbuntuLite doesn't come with a LiveCD for me to show a demo and multimedia codecs by default once I've installed it. It'll be troublesome in case if there's no internet connection available.
Then Puppy Linux came to the picture. It came with JWM window manager, which is something similar to Windows (again, I'm talking about from end user perspective) and according to Wikipedia, it is possible to run Puppy Linux on a PC with only 48Mb of ram. I've tested it on my neighbour's old laptop (TwinHead Slimnote VX with 192Mb ram with Intel Pentium II 300Mhz) and it works flawlessly. The .ISO image is quite small which is about 87Mb. Don't underestimate something that comes with a smaller size. Once installed, everything works perfectly including multimedia codecs and web browser plugins.
This is a perfect solution (at least for me), to promote Linux to my friends and family, especially those with an old machine and no internet connection available. DivX and mp3 files can be play out of the box. All I can say is...I'm very happy with the distro :D