i just want to know if the new ubuntu (12.04LTS) can fit perfectly on a normal cd :)
I stopped burning a CD (or DVD) for ISO files about 2 years ago.
A cheap 2GB Flash USB drive is 3-4 times faster for installs, and can be repeatedly reused (for later releases).
You can install from a normal CD:
http://www.ubuntu.com/download/desktop/install-ubuntu-desktop