I was handed a machine running this (4 or more years old) Linux distribution to update & make shiny today.
Other than the old version of URPMI (Mandriva's package manager) not knowing rsync:// URLs, it all went smoothly — the machine is now a Mandriva 2006.0 box and awaiting some more RAM (it only has 128MB), all without me signing my life away in blood or hex-encryption. Amazing stuff.
A few index updates & the command urpmi --auto-select makes it all look too easy.
I can’t picture it being much more difficult with any of (say) Debian, Ubuntu, Slackware or SuSE either.