I have a 2005 mac ibook g4, the model number is a1133. a while ago it started flashing a question mark and the mac icon and would start up after a while. But it stopped booting and just kept on flashing that, i took it to a mac store and they told me it needs a new hard drive so i installed a 160gb hard drive but when i start it up it does the same thing. so i think and have been told i just need the install/ restore discs but i just dont know which discs to buy.????? os x 10.4 tiger?????? Thank you.