Some devices (Not many these days) don't have C++ compiler support for them. Having at least an understanding of assembly can help you debug tons of issues that could arise, especially with communication to hardware.
Thanks for all the input, I'm definitely keeping it all in mind.
As for me knowing basics, I do have help from a friend that's been doing electronics since the 80s for IBM and now works with me here. So he's been a great deal of help too.
I think I'll go with this: http://www.hobby-hour.com/electronics/lm2576-step-down-switching-regulator.php
And a battery like this: http://www.all-battery.com/li-ion1865074v2600mahbatterypcbmodulewith22awgbareleads.aspx
It has schematics for the circuit I'm trying to make too.
LP3853 looks like the way to go. The voltage drop was too unpredictable anyway. Thanks for the info.
Edit: Finding a place to purchase one isn't as easy though.
Actually, I might have found a better solution. 1N5401 diode seems to have a forward voltage drop of 1V, so I basically end up with 5V after the Diode, and since it's a diode, it can stop the batteries from being connected backwards anyway as a bonus :)
I'm dealing with a circuit board that requires 5V DC power and can draw as much as 2 amps.
I want to be able to supply this power with a rechargeable battery pack (Later a wall adapter to power it and charge the batteries).
I'm not an advanced electronics engineer at all, very new to it. I...