Ubuntu 12.04 minimal installation
Please give UBUNTU specific anwers because I know I can get the above configuration using Xubuntu or Lubuntu.
Firstly: Xubuntu is Ubuntu with xfce instead of unity. And lubuntu is Ubuntu with lxde instead of unity.
If you use the alternate CD (which has a much more detailed text-mode installer than the live CD), you get to choose exactly what gets installed, so you can install a minimal system and work from there. You can find it on releases.ubuntu.com.
You can also use the mini ISO. It uses the same installer, but is tiny, it downloads everything from the Internet: i386 or amd64