VR6 should have ABS and TC as standard.
When the car starts up the ABS light (right hand side, to the right of the light dial) should pop on for about 1 second and then go out.
If it doesn't come on at all: the previous owner removed the bulb to cover up a fault / the bulb has blown.
If it come on and stays on: faulty - get it checked!
Find an open stretch of road prefereably with a bit of water on it and drive along: even 10mph should be enough, start off slower if you're not sure, try a bit faster if nothing's happening. Make sure there's nothing to crash into (trees/walls on the sides, oncoming traffic, people travelling up behind you, etc, etc). Then drop the anchors!
Hold the brake pedal down hard and you'll feel the pedal pulse and vibrate under-foot. According to the manual "do NOT pump the pedal" as you would do on a non-ABS car... as it stops the ABS from working.
I've only had the ABS work in the last little bit of braking (when you stop braking progressively and are more likely to push the pedal down harder)... pretty easy if you've got uprated pads and discs and even easier if you've got naff tyres - I only fit one of these two categories. It should work fine at higher speeds too, but I've never needed it. Touch wood!