I am unable to take off an item. First make sure that the armor does not have any item worn over it. If you are wearing Plate Mail and a cloak, you will need to take the cloak off first. If this is not the problem you may have a cursed item. To remove this item you will need to buy and use a scroll of remove curse.
Most monsters have an alignment index which determines whether they are chaotic, neutral or lawful.
By killing lawful monsters your alignment will turn chaotic and by killing chaotic monsters it will eventually turn neutral and then lawful. Make sure that your character is not overweight and is not hungry. The dogs disappear with all the monsters and some NPCs during the reset. The dogs are automatically stored in kennel, you can retrieve them from local dog NPC once after the reset. Although you do not have a collar, you should be able to get the dog back for free.