You can install WinXP right to your Mini without using OSX at all. That's exactly what I'm doing. The bootcamp drivers are on and accessible to Windows off the Leopard or Snow Leopard disk. I have the drivers on a thumb drive so I don't have to be bothered with the disc.
Not using virtualbox, or vmware fusion or parallels is 1000x better. Way too many issues virtualizing windows within OSX.
yeah check out refit it is a nice tool that will let you switch oses on boot much easier than the standard apple method. it will automatically give you the menu to choose which os you want to use, without having to hold down the "option" key first. this tool will also let you do a tri-boot if you so desired.