Strange thing happened. I want so sell my old Macbook and therefore used a disk image of the Snow Leopard DVD that I restored onto an external drive. I booted off the drive and went through the installation steps.

Now I really would like to perform "archive and install", as there might be some files that I need later, but I didn't see the option. The only options for installation I had, were, including others, optional printer drivers and Rosetta. So I just clicked through and I wasn't given any other option.

After about 45 minutes, my system booted again, and voila, there was my old system. Nothing changed.

How should I proceed to actually reset the system? All I have is that Snow Leopard DVD image.