Your best bet would be to use the Linux Installer applications to install the distros. Android is already a Linux based OS, but to boot an actual version of linux instead of an Android ROM you'd need to change alot. You'd have to have a custom bootloader, have patches to the system so it will mount the proper partitions during boot, and you'd need the drivers for the phone's screen, etc. The only problem with drivers are that you wouldn't be able to use the Android ones since their linked with bionic instead of glibc (afaik). Without the right graphics drivers, X11 won't start and without X11, Gnome/KDE won't start either. You'd probably get XFCE (If you even make it far enough to get X11 working) or at best, Blackbox or Openbox.