Speaker system

Does everyone agree? No. At your price point it might be good to go to Best Buy and pick out something to put together. For your room size, the speakers you suggest would be worthless. If you just want some sound in your room then have it. But it would require some power and some good sized speakers to really get your room cooking.

You will need at minimum a pair of Klipsch LaScalas to have a chance at filling that space but since you don't seem to want to answer some basic questions it's going to be impossible to help you. 

Headphones?

does the room have walls? Roof? Or just a fence around it?