newbie here -- HELP! -- which one of these subwoofers is best for me?

i do not have a sub, here is my setup.

about a 15x20' living room
my system will be more used for video games and blu ray, not much music

Fronts, two of them:
http://www.newegg.com/Product/Product.aspx?Item=N82E16882290204

center:
http://www.amazon.com/gp/product/B002778F88/ref=pd_lpo_k2_dp_sr_1?pf_rd_p=486539851&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B002778FAQ&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0TPFYWY1BRHNAA0R1QH4


receiver

http://www.newegg.com/Product/Product.aspx?Item=N82E16882117409&Tpk=pioneer%20vsx-822


sourounds: two them

http://www.amazon.com/Boston-Acoustics-SOUNDWAREB-Soundware-Black/dp/B000UTNQWA/ref=sr_1_13?s=electronics&ie=UTF8&qid=1352311956&sr=1-13&keywords=boston+acoustics



still need sub

Which sub should i shoot for?
i do'nt want to spend over 200, really d'ont want to spend 200
need to have it auto turn on when i turn the receiver on

couple choices i have found

http://www.amazon.com/Surround-Theater-Powered-Active-Subwoofer/dp/B0052OGTBS/ref=sr_1_5?ie=UTF8&qid=1352313556&sr=8-5&keywords=subwoofer+12+surround+sound

http://www.amazon.com/Polk-Audio-12-Inch-Powered-Subwoofer/dp/B000092TT0

http://www.amazon.com/BIC-America-F12-475-Watt-Subwoofer/dp/B0015A8Y5M


please help me choosE!!
thank you so much
Edited by ryanderenzy - 11/7/12 at 12:50pm

ok, looking for best 12" powered sub(probably want front firing, front port, as i'm gonna put it against a wall) for 200$ or less

using polk 50's as fronts, polk center
panasonic reciever fsx-822


thoughts on sub? thanks