Here is how you can compile the mother of all editors on Ubuntu 10.04 from source:
1. Obtain the source archive for Emacs from ftp://ftp.gnu.org/gnu/emacs/
2. Open a Terminal in Ubuntu and type:
A. sudo apt-get install build-essential libxpm-dev libgif-dev libtiff4-dev
B. This will install the necessary packages to compile Emacs.
3. Extract the Emacs archive downloaded in step 1 by typing: tar xvzf emacs-major_version-minor_version.tar.gz.
4. Change to the Emacs source directory. a.k.a. cd emacs-major_version-minor_version
5. Type: ./configure
6. Type: make
7. Type: sudo make install
Enjoy.