Was thinking of making individual posts, but one shoud do!

Fristly, What exactly is Mental Ray? How does it work. I noticed it is faster than software, but I'm not using details so I would imagine that software is THE better option, but is much slower. Software seems more better also, because you can always just add code to effect rendering. I understand that - but exactly how does the Mental Ray work?

Secondly, how do I get Hardware rendering to work? I can get Software and Mental ray to work, but just get a blank screen on Hardware rendering?

Thanx in advance!