The Option key is the one that opens the boot options when you start up the computer, it's a necessity for Boot Camp
Alright.. so yesterday I got my iMac, and today I attempted to install Windows 7....
Well.. thats all very good and dandy, but when it came to insert my MacOS CD to install Boot Camp... it gives me an error 2229... which basically prevents me from installing it and getting back into my MacOS... heeeelp =)
Boot Camp Assistant should already be installed.
1) Open Finder, go Applications -> Utilities -> Boot Camp Assistant.
2) Partition your hard drive using the on-screen instructions.
3) Insert the Windows 7 disc that you should have made beforehand.
4) In Boot Camp Assistant, press Start Installation. Your computer will shut down, and will automatically reboot from the Windows disc.
5) Follow the installation instructions. When it asks to pick the partition, select the one that says BOOTCAMP. It will say it isn't formatted properly, so click on the Options button and press Format. Continue the installation.
During installation the computer will reboot several times. When it does, you have to hold down the Option key and select the Windows partition each time otherwise it may automatically boot back into OS X, which you don't want.
Once Windows has finished installing, boot it up by holding down Option and selecting Windows when you turn your computer on. Now you can insert the OS X disc and install the Boot Camp drivers (this basically allows Windows to work with the hardware in your Mac)
Hope this helps