To answer your first question I have to ask what your helicopter experience is?
If you are new to helis then either get a sim and learn using RADD's at: http://www.dream-models.com/eco/flying-index.html
This is the best way to learn your controls. Sims keep you from buying lots of replacement parts. :-)
To answer your question about inverted flight-- You flip the switch on the right side of your TX called the idle up switch. This switch changes your pitch and throttle settings. Never flip the switch while your heli is sitting on the ground with the battery attached. With the TX idle up switch pulled towards you, you will find that the throttle at the down position is at full throttle in negative pitch and will burn out your motor as well as possible damage to other parts.
This switch is only to be flipped while you are in flight. At half throttle you are at zero pitch (approximate). At full throttle you are at 100% throttle and positive pitch, at zero throttle you are 100% throttle in negative pitch (for inverted flight). There are a lot of variables to this but I believe that my explanation is long but to the point.

Michael