Can i program arduino ng with the same code as for programming arduino uno
Yes, within the flash memory size resistriction of the specific chip installed on your NG board. Early versions used a atmega8 chip and later versions used atmega168 chips. That is why there are two different arduino NG board choices avalible in the IDE menu. Also nothing prevents you from inserting a atmega328 chip onto the board if you wish, you just have to select the standard 328 type board.