In reply to gigahurtz.. reply w/ quote not working..
I will try that, I know that helps on channels like Weather and any sports channel to block the interactive features.. when watching DVR'd events that wouldn't work so well though. I'll say that the sluggishness has increased since the HD GUI releases have been packed with all their existing features. The 1st round of updates were blazingly fast.
Try doing back to back resets, that has worked for some.