headphones are a very personal thing...and every set is different. there is really no "best" set of headphones because different people like different sound signatures,,,more on this later.
you should know that, generally speaking, 5.1 or "surround sound" headphones are regarded as gimmicky and are nowhere near the quality as phones from brands like sennheiser, beyerdynamic, akg, audio-technica, etc.
HOWEVER
if you are happy with the way they sound and they are comfortable, that is all that matters. i cannot stress that enough. there is a forum i frequent which deals solely with headphones (
www.head-fi.org)... the people there suffer HEAVILY from "upgrade-itis". that is to say, they will buy a new set even if they are satisfied with their current pair, just for the sake of curiousity and/or the possibility of better sounding audio. it is a very expensive and addicting hobby... that being said, if you do want do dabble a little, there are a few things we should know:
how much are you willing to spend?
what type of sound signature do you prefer? warm and bassy, bright and detailed, or neutral/balanced?
do you prefer open or closed headphones?
are these strictly for gaming purposes or will you also be using them for portable music purposes?
if you can answer these questions i'll be able to assist in narrowing your selection down.