There are lots of commands to find out your ditribution name and distribution version. Some work on some distros, some work on others. Here are some of the methods:
lsb_release -a
cat /etc/*release
cat /etc/issue
cat /proc/version
uname -a
One of these methods will surely tell you your linux distribution name and current version.
Linux is awesome and so is the terminal. Things become a lot more easy if you can just type in few commands and get your work done. Downloading youtube video has always been messy with GUI downloaders, browser extensions and web services which claim to give you the download link to that video. Now, you can download it from the terminal using youtube-dl in ubuntu. You can also download and install it in other flavors of linux. The script is written in python.
Install youtube-dl from the official repository in Ubuntu: