Hi ClessxAlghazanth,
It really depends. I'm using a 64bit OS, but I stick with the 32bit version because it has the Enhanced/d3d blitter. For really resource-intense things, 64bit is the way to go, but, fbneo isn't very resource-intense at all. On the other hand, since all PC's & cpu's aren't created equal: your best bet is to try it and see if you like it better.
best regards,
- dink