Ubuntu's page https://help.ubuntu.com/community/In...esktop_Edition says:

The Recommended Minimum System Requirements, here, should allow even someone fairly new to installing Ubuntu or Gnu&Linux to easily install a usable system with enough room to be comfortable. A good "rule of thumb" is that machines that could run XP, Vista, Windows 7 or x86 OS X will almost always be a lot faster with Ubuntu even if they are lower-spec than described below. Simply try Ubuntu CD as a LiveCD first to check the hardware works.

Ubuntu Desktop Edition
700 MHz processor (about Intel Celeron or better)
512 MiB RAM (system memory)
IMHO this info is outdated; it might have been true for Ubuntu 10.04, but for the current Ubuntu Desktop version (12.04+), I would recommend 2 GHz with 2GB RAM as a minium to run it comfortably.
FWIW: I do use Ubuntu 12.04 on a Netbook (1.6 GHz Atom, 1 GB RAM), and technically that works, but not "comfortable". So I'm considering to install Lubuntu on that system.

So: what do you think about the Recommended Minimum System Requirements to run Ubuntu 12.04+ comfortably for someone fairly new?