Ok Update:

I reinstalled Chameleon, opened Terminal and typed (following another guide):

sudo -s
fdisk -fboot0 -u -y /dev/rdisk1
Which did not work. It said it cannot find the partition or something.

Then, I tried another LAN Atheros AR8121 kext, loading it with Kexthelper.
Then, I opened EFI Utilities and took the Geforce 8800 GS device, changed the name to Geforce 9600 GSO in the hex and saved to com.apple.bootlist or something.
Then, I rebooted.

Again, I had to boot from DVD. The atheros kext didn't seem to work, I still did not have internet. Neither did the thing with the Geforce 8800 work. I still have 800x600 resolution and cannot change.

So, I tried to boot into Windows, but before startup I got stuck at the blank screen with blinking cursor at top left. I put in Windows CD and went into repair and typed fixboot and fixmbr, which resolved the problem. Windows working fine again.
Out of curiousity, I rebooted again and tried to boot OS X from the external HDD and not from the DVD. The Boot0:done and Boot0:MBR thing has disappeared.... but I am stuck at the blinking cursor now.
Booted into OS X again from DVD, but now my mouse and keyboard don't work anymore!

Help please! I'm really trying here lol

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