EMACS is my standard editor but I don't know what several of these things do. I'm open to my environment being improved but I'm not so into installing something

EMACS is my standard editor but I don't know what several of these things do. I'm open to my environment being improved but I'm not so into installing something when I don't know what it does. The site doesn't do much to explain what I'm installing or what it'll change about my current setup. I actually setup a new computer yesterday. I copied my .emacs file and used ELPA to install js2Mode. This minimal setup probably heavily influences my lack of trust in installing what appears to be three or four different things all stuck together. Note: http://emacs-bootstrap.com/#second http://emacs-bootstrap.com/#second, the init.el link leads to a 404.