Bootcamp Install Windows 7 Expanding Windows Files

Hello everyone!
I've been trying to install Windows 7 Ultimate via BootCamp on a late 2009 iMac for several hours now to no avail.
What happens is, I boot from the Windows 7 install DVD and the installer appears. I can choose between 32-bit and 64-bit windows and format the BootCamp partition as NTFS. It's when I click 'next' on this dialog that the process wrong.
The installer just skips the 'copying windows files' part of the installation and just stalls at 'expanding windows files'. I've tried leaving the computer alone for over an hour and it just stays at 0% doing nothing.
I've downloaded the Windows 7 drivers for late 2009 iMacs from Apple and put them on a FAT32 formatted USB-stick with an MBR partition table, this does nothing for me.
I've tried to restore and recreate the windows partition via BootCamp.
I've tried to install both 32-bit and 64-bit windows.
I've successfully managed to install Windows XP on the computer.
Nothing I do seems to work, I just can't get Windows 7 on this machine!