Yeah, counterattack-based combat is pretty hard. With enemies like Uhura, if you want to match your response to each of her 3 attacks, to either parry-riposte (vs normal attack), duck-rising-slash (vs high), or do the skullsplitter (vs low), that's pretty much unfeasable - if the game is running at its intended speed. Playing on Windows 7 often comes with a speed bug
and a slower framerate, though, which makes combat easier. HQ graphics filters also tend to slow the game down.
Your best bet with most enemies is to simply spam the attack combo whenever you see an opening, and jump back or shield-parry if you need to. If you're playing with a shield, that will block almost everything from weapon-using enemies, so just use that. With the Terrorsaurus and the Ghoul, you want to simply run away from them until you've build up your skills enough that a simple offensive strategy + jumping back when needed (+ anti-ghoul boots) will work.
Another way to add some variety into your fights, is to respond to every attack by quickly tapping Special-Back-swing. This covers all possible attacks from enemies like Uhura, Terrorsaurus or Scorpion, and will result in skullsplitters when facing a low attack, and either rising-slashes or jump-backs in other cases.
Another such combo is Special-Parry-stab, which produces skullsplitters and parry-ripostes, but doesn't work against animals.