I rarely shoot sports, so I'd advice checking out the Sports section here:
Your kitlens will be good for sports if you can get up close to the action. If you need some distance between you and your subjects, you may need to get that 55-200mm, or indeed any other telephoto lens.
I'd suggest to never use Auto ISO, but if that's easier for you at the moment, you could. Maybe you can limit the values Auto ISO will choose (to, say, ISO 1600). That way, you won't end up with too noisy photos.
- Bjorn -