Andi
Yes, these are the right terminals to use. The +ve terminal should have a plastic cover over it - it's attached by a thin piece of plastic to ensure that you don't lose it, so it's worth checking just under the +ve terminal to see if it's there. (Mine had fallen off when I bought it, but was still hanging there).
You can use any piece of the bodywork for the -ve terminal, although the one you have marked is designed for this.
If you have an ///M, then getting at the battery terminals is a major pain - hence why BMW provided these terminals.