1. No i don't believe Warriors have the use of healing magic, or any magic in that matter, i think you may have to use healing potions, so try get in a party with a priest for some free heals and fast leveling
2. I have experienced the game completely exiting randomnly and getting a little error message and some other random writing, but i just deal with it. I am using Windows XP Media center i believe, and i have the graphics on high. Maybe for you, since you get them so frequently, lowering the graphics is a good idea, also lower the distant view meter.