Linux

Hey,

weird story, dunno if this is actually possible, but here's what happened: My dad's PC (Windows) is completely full of trash, the hard drive is completely full. After the last Windows update he wasn't able to boot anymore, even from a WindowsCD it didn't seem to work. That's at least what he told me, haven't been to his PC yet.

Anyways, my idea was to use a very tiny, leightwight Linux distro that is bootable from a live CD to save his important data, clean up his hard disc and try to repair his system.
So my question: Any ideas which distro to use? Again: I do not want to install it in the first place, it has to be bootable and workable from CD

A gentoo-x86-minimal or gentoo-amd64-minimal livecd ought to work. It boots to a raw root command prompt. The install procedure for gentoo is still manual, so these livecds don't install for you.

Puppy Linux would be my first port of call. About 100MB is tiny enough?

Puppy is excellent and slitaz, both run in root.

I would also say Gentoo

I would not call Gentoo a 'minimal' installation in terms of space. In one sense it's minimal, you get to choose your own software and features, but it builds its own kernel, which that takes considerable space to do in of itself, and the portage tree is another gig or more depending on your filesystem. I've installed an entire Gentoo system it in 1GB or so before but that required dirty tricks like unionfs+cramfs filesystems.

You could install putting /usr/src, /usr/portage, and /var/db/pkg on external filesystems though, and just unplug that when you're done, which will remove the space bloat.

Gotta throw DSL in as well.