I was having the same problem. This may sound crazy but as I was scrolling the posts I started to press the screen a little harder. My tablet slowly started gettting back to speed. Try this….apply more pressure while typing, pressing, or scrolling. I purchased this Samsung T807 at a pawn shop today. It was freezing up as soon as I got it. It hasn't frozen once! Go to setting and change the screen sensitivity.
# Settings
# Displayed
# At the very last option check “increase touch sensitivity”
# Hope that helps.