memory

hi new to the site building my own pc
cosmos coolermaster case
evga122ck-nf67T1 mb
q6600 g stepping proc
ncua nh-u12p heatsink and fan
2wd 640g hd
antec650 ps

my question is i bought 2 sets of corsair dominator memory
4x1gb (because they were cheap at the time . model is C4D 6400 the thing is one set says version 2.2
and the other set says version 1.2 i understand that the 1.2 version is better for possibly overclocking
because it has the micron chips.is that so? will 32bit vista run good with only 2 gb if you have a decent processor
will 64bit run good with 2gb installed same scenario. was going to put all 4 sticks in but reading the posts 4 sticks versus 2 causes problems sometimes.
if this doesnt work i will have to put in just 2 gb .and will 2gb overclocked help the absence of the the other 2gb i cant put in? thanks alot for the help .1st new build gets confusing sometimes.