Does your computer have analog audio outputs? If so, I would get a pair of powered monitors like
these guys. They will have high sound quality and also decent bass output. This is a solution in which a much greater percentage of your money going into sound quality, rather than a lot of janky electronics like an entry level AVR. If you spread your money out across speakers, and an AVR, and a subwoofer, you will have a lot of stuff, but it wont sound as good. Just getting a pair of powered monitors will make setup simpler and make for a better sound.