HP - set the value so high that it auto-hides. For 4:3 monitors, this is about 10000. For widescreens, I have no idea. Needless to say, this makes it impossible to use hit points in your map.
Armour - set the "Armor:" text in game interface to ",s". This will also hide the armour value. Set the icon to some imported black image.
Status - as above, set the "Status:" text in game interface to ",s". This will not hide buffs. To hide buffs, set each one to some black image.