running media portal on an older PC which needs a cpu upgrade to run 720p (working on that) but my question is, if i intend to ONLY use this pc for media portal and internet explorer (and maybe the occassional older flight sim) is it worth sticking with 32 bit xp with sp3 or putting vista on this htpc? will it make much difference to media portal performance? keep in mind that the hardware is 64 bit compatible.