[Kidd2323]

I don't think, if Fingolfin defeated Sauron, that he would have been able to destroy the ring. In one of Tolkien's letters he states (although not exactly) that ultimately every elf, dwarf, man, hobbit, orc, etc. would fail in throwing the ring into the Crack of Doom. They would with good intentions claim the ring for themselves and eventually become evil in the end. The best a being could do was to refuse the ring; therefore, having touched the one ring, Fingolfin would have eventually failed to destroy it, but on topic, I think he could have defeated Sauron in battle--Sauron being Morgoth's lesser, Fingolfin being (in my opinion)the greatest elf ever.