I beat the game on "Normal" difficulty without using any potions. Not bragging...I just thought I would save all the potions until the final boss, and then I ended up not needing them.
It took me about 11 hours total, and I only had to look at a walkthrough twice. I had the same problem as you Connors, the tutorial didn't mention how to attack so I got my butt kicked by the giant snail. I'm currently playing a custom dungeon that's a lot harder than the main game, I've spent 12 hours on it and I don't think I'm even halfway through.
Hit Tab to view the auto-map. Left click on the auto-map to add a note for yourself. It's really useful.
My advice is to focus all your characters on one different attribute. My Human had most of his points in swords and armor, my Minotaur had mostly axes and armor, my Rogue was a throwing-weapon specialist and my Mage specialized in fire. In this way you can deal the maximum amount of damage. Also, if you haven't figured out how to "skirt" enemies, you basically just hit them and immediately move out of the way, then repeat. Later enemies can't be beaten by simply standing there and absorbing their hits.
Zoo...I think I remember the room you're talking about. I almost quit right there. If I remember correctly, the trick is to stand on a square where you're protected by walls on three sides, and then have your two strongest characters up front to take the blows. I was eventually able to make it through the fight without anybody dying, but it took a few tries. There is a way to bring characters back to life, if you haven't discovered it already.
