The most traditional Windows is the 64 bit version, with the most optimization. You really only need a 32 bit system if you either, A. plan to run it on an older 32-bit architecture processor, or B. Just want to spend less (?)... there's no real reason to get a 32 bit OS in this day in age. 64 bit is the way to go, and yes, it does eat up some available RAM, but so does the 32-bit.