Version 11.4.402.265 or later is for Snow Leopard onwards. The latest version,10.3.183.23 or later, is for Intel Macs only running Tiger or Leopard, as Adobe no longer support the PPC platform. Note that version 10,1,102,64 is the last version available to PPC Mac users*.
You can check here: to see which version you should install for your Mac and OS.
