To check the ABS, stomp on the brakes on a somewhat slippery surface - ice, snow, or sometimes even just wet streets.
As far as VSC, that's a bit more difficult. It's designed to keep the car going straight down the road, correcting for over-compensation on your part. I've intentionally applied too much gas going around a corner in the snow and made it fishtail. The computer reacts, but I'm not sure if that's VSC or TRAC (traction control) doing its thing.