im buying the house i live in. most of the outlets are two slotted, one small slot, one large (polerized?) i pulled the cover off one outlet, it only has 2 wires going to it, metal workbox, but not bx, they run romex, w/no bare ground. i check the voltage from black wire to workbox, no voltage. does this mean that the outlet is not grounded? no voltage from white to workbox either, but thats correct, i beleive. i want to replace all the outlets with 2 slot/ground hole, mainly so i dont have to use adapters to plug in some appliances. i realize they will not be grounded, but if i install GFCI breakers, and mark each outlet NEG, will this be up to code? i also realize that GFCI breakers do not constitute a ground either, but will make the ungrounded outlets safer. please advise. btw. anything i change will be after i purchase the house!