Does the Arduino chip get wiped of any (uploaded) code when you press the reset button?
Can you retrieve the code that is currently on the chip?
No, nothing gets wiped and yes you can read the code and data currently on the chip. You do lose the contents of RAM when the chip loses power. Avrdude is a useful program that will allow you to read and write the chip contents. The Arduino IDE uses avrdude to program the chip. Lady Ada has a very good tutorial on Avrdude - indeed her tutorials are all very good.