Final answer:
The planet with the second most extensive ring system after Saturn and no notable surface features is Uranus.
Step-by-step explanation:
The planet that fits the description of having no notable surface features but possessing the second most extensive ring system, after Saturn's, which were discovered from Earth is Uranus.
Unlike Saturn's rings which are broad and mostly water ice, the ring systems of Uranus and Neptune consist of dark particles confined to a few narrow rings with broad empty gaps in between. Jupiter's ring system is a transient dust band, while Mars has no ring system at all.