As with all Dragon Quest Heroes, the Hero has no default name. The Hero is the son of Papas and is quite a well rounded character. He excels at the healing arts and is present throughout the entire story.
*The Hero learns this spell in Ruraphin for getting the Moon Herb
Bianca is a fairly good magic user that has some physical strength too- not as much as you'd hope for by the end though. You originally meet her in Alcapa when Papas takes you there, and you meet her again later when you search for the Water Ring. She is one of the choices for marriage.
Flora is the other girl you can choose to marry. She is better with magic than Bianca, but she isn't as strong. You first meet her in Salabona and participate in the quest to find the Ring of Flame and Water so you can marry her. You do not have to marry her after you get the Rings though.
The Son is the Legendary Warrior- able to equip all the Zenithian Equipment that you find. He has a very nice attack power and is also quite good with magic, though not as good as his sister. He is destined to destroy the Demon Lord and return peace to the land.
The Daughter is the more magically inclined of the children; thus, she isn't as physically powerful as her brother. She has some exceedingly helpful spells such as Explodet, so it's nice to have her around when you need some heavy offensive magic.
Sancho is Papas's servant- he helped take care of you when you were little. He joins you in Granvania and can be picked up at Ruida's. He's strong physically, but the rest of his stats aren't very good. Give him the Demon Armor for good defense- the 0 Agility isn't much of a difference than what he has.
Pippin is a Granvanian Soldier that wants to travel with his King. You can recruit him along with Sancho in the 3rd generation. Pippin learns no spells- he's purely a physical fighter.
Henry is the Prince of Reinhart. He later joins you after the escape from the Great Temple. Henry's an interesting character- he's decent at both physical and magical attacks though he excels at neither. He's not with you very long either.
Papas is your father. He's almost purely a physical fighter, and you cannot control him when he joins you. He's with you briefly in the very beginning of the game and later as you save Prince Henry.
Bella is a fairy that comes to Santa Rosa to get your help. With her, you must solve the problems in the Fairy World. Her powers lie only in magic. Also, she cannot gain any levels.