Well, that's maybe a bit TMI. But hey, there's no dress code here on the Arduino forum 
It is very unlikely this condition is in any way related to being connected to a Mac. This usually means either that the circuit connected to the Arduino board is drawing lots of current, or else that there is internal physical damage to some component on the board that is causing it to draw too much current (e.g., a short circuit).
The first thing you should do is disconnect the board from the computer and any other power sources and do a careful examination to see if you can spot any problems. That could be some change to the circuit that occurred since the time it was working, or perhaps some conductive debris that is causing a short.
If you can't spot the problem, you can try removing all the external circuitry and see whether the board alone will still get hot when powered. If it still gets hot, then the board is probably beyond economical repair and should be replaced.
The Tools > Programmer menu selection is only used when you are doing Tools > Burn Bootloader or "Upload Using Programmer". When you're doing a standard "Upload", the Tools > Programmer menu selection is completely ignored. So it makes no difference at all what you have selected from the Tools > Programmer menu.