RPGs are basically defined by a shounen-manga formula: You have powers. You walk around with a group of people until you get attacked. You may have turn-based attacks or not, but group members attack.
...Harvest Moon is much more of a sim game, in my opinion~ Nothing wrong with that, though. ^_^
I like adventure games... they often get confused with RPGs. Zelda, for example, is an adventure series. They're good, but not the same as RPGs. However, I'll find out in a month whether Japan knows the difference or not when I order a game listed as "adventure" that looks conveniently like an RPG. XD