Do what I plan to do today (or anytime I have a new car and it snows). Find a big, open parking lot and test out how the car reacts to locking the brakes, slides, etc. Try to be low-key about it but it is essential to learning how a new car will react. As for ABS, the MINI system is pretty advanced. Just keep that foot planted on the floor - seems totally wrong at first but it works.
Jason