OK, now thanks to JesterDev's manual OS X and Windows 7 now work! ;)

However, there is a minor problem:

Darwin Bootloader automatically boots OS X when the countdown is over - but I want Windows to be the default!
I've already searched a bit and tried
which caused a total crash of OS X.

As an alternative I could also use the Windows Bootloader (actually I would even prefer it), but when I choose OS X in the Windows Bootloader nothing happens - I only get a black screen!

I've also read that Darwin always boots the active partition, however when I set the Windows partition active the Windows bootloader comes up! It also comes up when I select Windows in the Darwin Bootloader.

To sum it up: I either have to repair the Windows Bootloader to boot OS X, or I somehow delete he Windows Bootloader so that Darwin is the only Bootloader and I can set the Windows partition to active and therefore as teh default boot.

Hope you can help me! Any answers appreciated ;-)

Has nobody an idea as to hot to delete the Windows Bootloader :eek:

fdisk /mbr ?

I think you're mixing up things, you cant delete windows bootloader, windows obviously wont boot without it, you are confusing the bootloader (the one who kickstarts the os) with the bootmanager (the one who lets you choose which os to boot) that is active and shows the boot menu.
The boot partition determines which bootmanager is active, but when you choose to boot windows in chameleon, you would still see windows bootmanager.
In latest versions of chameleon you can set the partition to boot by default using the "Default Partition" argument in the boot.plist, you would have to change that to your windows partition