Using an external power supply

Well, I bet this question has come and gone more than just a few times already, however, I could not find what I am looking for.

I am gonna need a bit more juice for my projects, so I got myself a 12vdc 2Amp power supply. q1: Now, if I hook it up to the Arduino, it will convert it to 5vdc and a bunch of heat through the voltage regulator, right? q2: Will I be able to get the full 2 amps through the Arduino (5v pin)? Or should I power the Arduino off of something else and get a voltage regulator in my circuit, so I can get it to 5vdc, and hook up the psu to the circuit itself? q3: Did I understand correctly that the vin pin on the Arduino bypasses the voltage regulator? So that would give me access to the 12vdc/2amp? (don't need it now but could come in convenient for later projects).

I've read funky stuff about burning the board when drawing too much current through the copper lines and such, so I just want to be absolutely sure that I won't kill my board when I try sucking alot of current through it.

Probably very newbish questions, but I couldn't find a satisfying answer/ answer that I could understand and I don't want to take the risk releasing some magic smoke from a €30 board :) Thanks!

q1- right q2- no, about 600mA is all you can get due to the regulator over heating q3- no, there is a 1A diode in the way so you can't get 2A.

Great, thanks!