I'm sure there was a hack on Vista to get HD working, but that's a very distant memory now.
I've been using MCE since November 2006 roughly around the time that the Beta version of Vista was available and then quickly moved to W7 when the Beta was released.
It's been known for a long time that MCE will eventually be retired which is a shame. So I've been looking at alternatives and will probably settle on Mediaportal TV Server along with Kodi installed on Amazon Fire TV. Where I keep full PC's I have the choice of MP or Kodi. The advantage of this is just my server will do the recordings and every other PC or Android device will be able to schedule recordings, watch recordings and live TV. The only slight down side is series record is not quite so good/easy.