you need the keys for VAG cars, i used keys from a polo, 2 small things which go into the slots at the bottom of the cd player under the numbers i think. you push the keys in then give the cd player a good pull and it should come out.
you may need to buy the ISO conector converter thing depending on your after market dvd player.
when putting the dvd player in it will be very tight at the back where the wires are, so be carful not to force it too hard.
regarding DVD player, once i did fit it, i found it anoying that it covered the de-mister ect when the dvd screen was out, so i swapped the empty pocket to the top and put the dvd player at the bottom.
also, just as a peice of advice... if you have a tuned TDI
ibiza with torque like mine... be sure to put the screen in before you put your foot down! ... i had to learn the hardway and nearly snapped my screen.