Hi, when you load up your Windows Setup (From boot useing the CD not from Windows.) Wait for it to load, then the window pops up asking you to press enter to install. And if I'm not mistaken you need to press F8 to accept the terms etc etc.
Now another screen, showing your hard drive should show, if it has 2 or more in a list, you need to select them one by one by reading the instruction on the page itself.
In order to "Delete a partition" I think you need to Press "D." As I said, it gives you instructions on the same page. When you press D, it will ask you to confirm, and it will ask you to confirm it again. I think you need to press L for the last confirmation. Again, it tells you on the page you will be on.
Do this for all the partitions, if they all disapear once you deleted the first partition then don't worry, it means there all deleted.
Now you can proceed to installing windows like you did before. O, and select "Format useing NTFS - Full" not FAT32.