The "bank thing" is just discussing your different oxygen [O2] sensors on your exhaust system.
-Bank 1 sensor 1 is the O2 sensor on your rear exhaust manifold.
-Bank 2 sensor 1 is the O2 sensor on your catalytic converter [aka cat].
If the one on your catalytic converter is giving you a code you may have a bad cat if im not mistaking. [can anyone corroborate this?] Your symptoms are smiler to a bad cat. I beleive a bad fuel filter would also give you a smiler problem although most likely not the case because of your code.
Also Denso is the company where you can get your O2 sensor from. Iron Indian is giving you a site, a name brand and a coupon code so you can order an O2 sensor online for cheaper then local stores.