PPC is PowerPC, a processor family that is not compatible with Intel (and AMD) processors. I think it was Motorola that first developed the PowerPC processors as successors to the 68000 line of processors. The 68000 was the processor that powered home computers like Commodore Amiga and Atari 520 and 1040 as well as early Apple Macintosh computers.
i586 is an Intel (or compatible, like AMD or Cyrix) Pentium class processor.
Some much for computer history, back to your problem. If you have a standard PC (that used to run Windows) then you want the i586 packages. Did you download an ISO file? How did you burn it? The ISO file is a CD image that the burner software must unpack when it's burned. If you look at the CD from inside Windows, do you see several files (RIGHT) or only one big ISO file (WRONG)?
Is your BIOS set to boot from CD?
P.S. No question is too stupid. Keep asking