thanks for the guide

I guess the reason you format the whole disk, and install windows again, is to have it as guide?

I really don't want to install my windows xp again, I have a lot programs and stuff there and it will take some time to install it again + I'm not sure if leopard will work, so all the work could be for nothing.

would it be possible to get this running without reinstalling windows
because I do have 3 disks:
disk 1: windows installation
disk 2: Partition 1: Mac OS journaled Partition 2: NTFS (I could use this whole disk if needed)
USB Drive: Mac OS journaled ( I had installed tiger on this one with no problems)

I also could remove my first disk and try to install leopard only, to see if it works on my computer.
But will there be problems when I connect my first drive again? Will I be able to boot in win xp again?

yeah you can install it do a different disk that guide is for one drive with two partitions