if you push and hold your traction control button, the light in your cluster will come on indefinitely. This means you have it disabled. If your tires start to slip when accelerating too fast (assuming you don't have it disabled), you'll see the icon blink 3 or 4 times, indicating it's engaging.
As far as the speed limiter, get a tune. I believe an sct can wipe that for ya. Why in the hell you'd need to go that fast is your own business, but that should do the trick.