need advice:surround speaker placement ?

i am planning for putting up my surround speakers, energy cr10, tomorrow in a 5.1 setup, ive read on here that side wall is better than back wall. the manual says to mount them at least 2 feet away from corner, in my setup that puts them right to the side, possibly a little in front of listening position (couch and chair up against back wall). is this something set in stone so to say, if i put them 16 inches away from corner will it be that big of sound difference??? also what should i put the speakers on, bipole or dipole, almost all listening will be tv or movies...