BootCamp + Windows XP SP1 = Epic Phail
Well, unfortunately for me I ran across a problem while using my gorgeous 20-inch aluminum iMac Intel Duo I purchased somewhat recently. I decided that I would install Windows XP through BootCamp, even though I already had Parallels with XP on it. (What was I thinking?) So I start it up, get the installation going, but when I go to pick the partition, it was looked quite odd to me seeing that there was only one partition and it was much larger than I set BootCamp to give Windows. So, I exited thinking I’d avoid problems.
Wrong.
Upon restarting the computer, it was rendered nearly useless. The only thing that I saw was a blank white screen along with the familiar sound of the Apple start-up noise. I pretty much panicked. It wouldn’t load from CD, it wouldn’t recognize anything (including any operating system whether it be Windows or Mac) and to make it even worse, there seemed to be very little help available online to help fix my problem. So there sat my Mac; a very pretty paperweight.
For the next day and a half I searched the Internet vigorously for some kind of solution. I did manage to find two useful articles. I took the two articles and sort of combined them to fix my Mac.
From what I can tell now, it is a problem with BootCamp and SP1 where it deletes or corrupts the partition map. Once I can put everything together, I’ll post an in-depth guide to fixing your Mac if it is experiencing a problem like I’ve had.
Oh, and for the record, I still and always have loved Macs, and this doesn’t change that. If anything it brings me closer to my machine. 
I did the EXACT same thing. Once I fired up the XP SP1 install, I couldn’t find the partition I had alloted, so I decided to exit. Same exact thing as what happened to you. I had to take my 24″ iMac into the Apple store where they ordered me a new HD. They tried to migrate my data but the partition was totally corrupt on my old HD. So, I asked for it back, hooked it up to an external enclosure, and now, as we speak, I’m running a data recovery utility and getting the data back. Don’t worry, all isn’t lost, you’re data is recoverable, but you’ll have to get your internal HD replaced. What a pain!
Ouch! That does sound like a pain. Well, luckily I was able to fix it without getting a new hard drive (as posted here: http://phail.net/2008/04/13/bootcampsp1-white-screen-of-death-a-solution/). That’s great that you got everything working again. I think Apple should try and make more of an effort to prevent people like us from trying an SP1 disc!
(Maybe disable install if it detects an SP1 or non-SP2 disc?)