Are there any additional classes and is there an object highlight key?

Pretty new to the Diablo universe here, so pardon me if it's obvious.

I normally like playing the holy warrior or guardian archetype, but the only heavy warrior seems to be the barbarian, and I don't care for its aggressive or, well, barbaric nature. So, the class I chose to start with is the monk. It's okay, but I still wish for something more like a heavily-armored traditional protector. I don't suppose there are any unlockable classes like this, or are the initial 5 classes it for the entirety of Diablo 3?

Also, is there a key for highlighting objects in the environment? I know that ALT shows you the actual items on the ground, but I'm talking a highlight for things such as barrels and other containers, even NPCs, just anything that has a label when you mouse over it. Is there a key to highlight that kind of thing?

It was a question. You don't know who I am, how old I am, or how experienced I am with games (other than being pretty new to the Diablo universe) or what I want or need from them. I appreciate the answers to the questions but not the overall condescending tone of your post.