In this video you will get an idea about how to install ROS on your Ubuntu system. Here I have installed ROS Hydro on my Ubuntu 12.04 (Precise) but if you are on 12.10 (Quantal) or 13.04 (Raring) then it is for you.
In the next video I will give you some basic idea about navigating files, nodes, topics and messages.
You can find link for ROS installation page here.
If you find any issues in installation or want to say something to me then I'd love to hear from you.