I hate to throw a serious wrench into your plans, but you need an Intel based Mac to use Boot Camp. It will not install or run on anything else, since the reason Boot Camp can work is because of the Intel Processor. Windows will not install, in any form natively, onto a RISC processor like the G4 or G5.
For BootCamp, the things you will need are:
• An Intel-based Mac (Currently either an Intel iMac, Intel Mac-mini, or MacBook Pro) running the latest OS version (10.4.6)
•*The latest Firmware update for that specific Mac. (downloadable for free from Apple's site)
• A copy of Boot Camp (downloadable for free from Apple's site)
• 2 blank CDs (One for the creation of the Firmware Restore Disk (in case of a problem) and one for the Mac-centric Drivers for XP that Boot Camp will create for you.
• A copy of Windows XP Service Pack 2 (no other earlier version will work) and of course a Product Key for said copy of Windows. Questionable legality on getting said key aside, you are supposed to go out and buy a copy. As well, it has to be the full version, not an upgrade CD.
• Wired keyboard and mouse (wireless may temporarily stop working in XP until the above mentioned CD of Drivers is installed in the latter part of the process).
• A few hours of time (Windows takes a while to install).
You will then start off by installing the latest Firmware update for you Intel Mac. Most were at version 1.0.0 when I did it, but I hear there is a new firmware version just released for most if not all Intel Macs.
Next, download and install Boot Camp.
Then, run the Boot Camp application, which should now be located in your Utilities folder. The Boot Camp Software will prompt you to create a Firmware Restore CD as well as a Drivers CD for Windows XP SP2. This CD is to add the needed Windows drivers into Windows XP for your Mac-centric hardware components.
BootCamp will next ask you to partition the hard drive. This is done (for the first time on a Mac that I've seen at least) in a non-destructive way. Meaning? It doesn't format the drive and then split it into two parts. It dynamically creates a second partition for you. A point to keep in mind is that a partition higher than 32GB must be done in NTSF format. Under 32GB and you will be able to FAT32 or NTSF. I never had that option, despite using 30GB as my partition, so I can't claim validity for that.
I should quickly note that you should be using a wired keyboard & mouse by this point. Wireless or Bluetooth keyboards may not function until after everything is set up (and Bluetooth may require drivers to be downloaded from elsehere to function.
Booot Camp will then prompt you to insert the Windows XP SP2 CD and reboot. At this point, your Mac will reboot and bring up the standard Windows XP installer windows. Click through and don't forget the valid (*coughs loudly at his own Mac*) Product Key.
Once Windows XP SP has installed, it will prompt you to restart (sometimes a few times, as Windows is fond of doing) and finally, Windows XP will be installed.
Now it's time for the Driver CD that Boot Camp created for you. Insert the disk and it should auto-run. Click through the steps and it will install the Mac-centric software driver components. At this point, wireless devices should begin to work again. However, the built-in iSight will not.
Windows will prompt for yet another restart, but once that has been done. Voila! Windows XP SP2 on a Mac.
I have some details set up here... Intel iMac and Windows XP?!?
I am currently testing some high-end games and am posting my results.