Among the features I've already disabled are Aero (seriously, who the **** uses this?), indexing. Others I haven't disabled yet are Libraries, generally removing the extra stuff from the new Windows Explorer, and the new stupid Start Menu. I'm still finding out new stuff to get rid of, though.
As for the tearing, only one of media player classic's output methods alleviates it somewhat, although not completely. Note that the tearing only shows up on the TV, not on the monitor. Usually, this is a result of low performance mostly affected by the CPU and GPU. On XP, I had the same sort of tearing before upgrading my CPU from a P4 to the current core duo.