140sqft isnt much, thats only a 12x12 / 11x13. you could do perfectly fine with a surround system with satellite sized speakers or a pair of bookshelves. my theater/gaming room is 13x14 so is not much larger and i use some satellites myself.
you did not list a budget. as for home theater surround systems, the energy 5.1 take classic is a good entry level set you can pair up with a cheaper receiver unit (AVR). the monoprice 10565 is a knock off of that set which also is not bad. expect around $250-500 depending on choices
if that is out of budget, its possible to get some dayton b652's, pioneer bs22 or micca mb42 along with a cheaper amplifiefr to make a decent entry level 2.0 hifi set at a more modest cost of $70-150
its also possible to use cheap speakers such as the 5.1 logitech z506 for $100 but they do not compare with hifi sets honestly.
you need to be a little more specific on your budget, location, needs, expectations, etc if you want a better answer.