If you want to run Windows only (which like somebody here, OS X is what makes a Mac a Mac), you should be able to do so by doing the following
1. Insert the Windows CD/DVD (if you have not done so, boot the computer so it can accept discs), then reboot
2. Hold down the "C" button during boot, or hold down either "control" or"alt/option" (I forget which) to go to the boot menu, and select the CD/DVD labeled "Windows" (typical "Boot from CD/DVD" keystroke for Macs) (you may get a message saying to press any key to boot from CD/DVD after it boot from the disc, if so, press a key on the keyboard)
3. Load the required files like normal, but when you get to your Hard Drive/Partition select screen, delete ALL available partitions, format the entire hard drive as NTFS, and begin install
4. After the Windows installation is complete, remove the Windows install CD/DVD and insert disc 1 of the OS X install DVDs, you should get dialog boxes saying that new hardware was found (all the Mac hardware), point each dialog box to the OS X DVD to find and install the drivers (do not install the EXE file on the OS X DVD, this is to install the BootCamp software and Startup Disk software if you were to use Mac)
5. The Mac should run entirely (minus seeing a BIOS, as Macs use an EFI, and the EFI doesn't show itself) like a PC, and automatically boot into Windows
There are some updates you will have to do occasionally (like the EFI update) that may require you to boot into Mac (if there isn't already a workaround to do it in Windows), in order to do these updates, you will need to install OS X on an external hard drive or flash drive, to do that, install normally, then when you come up to the Hard Drive/Partition selection screen, select the USB drive (it should show up a an orange box with the USB logo), then continue install (you will need to format the external hard drive or flash drive before you can install OS X)
Now the Mac should automatically boot into Windows when you boot normally, then when you need to make an update (you should check about every 1 or 2 months), connect the drive with OS X on it, hold down "C" to boot from the USB drive or hold down "control" or "alt/option" (again, I forget which), and look for that orange box with the USB logo that should be labeled OS X, it should then boot like it did when you first ran he Mac with OS X, keep the drive connected the whole time to prevent corruption, then when you go to shut down or reboot back to Windows, you can safely unplug the drive
