Currently taking crestor (rosuvastatin) 20mg and wish to stop; can I simply cease to take the meds?

Yes. You can safely stop Crestor (rosuvastatin) without a withdrawal reaction. However, you should talk with your physician about why you are on it and what long term benefit it might provide.
Yes. Yes you can stop. My question is why? Have you had an adverse reaction? Do you not like the "concept" of taking a statin? I would much prefer that my patients schedule an appointment to talk about it before stopping it. That way i can explain why I have prescribed and what the benefits are and discuss your concerns with you. The physician-patient relationship should ideally be a partnership.