tolkiens legendarium - Was Sauron's body destroyed before or after the ring was cut from his hand?

I'm a bit confused as to the ordering of events leading to Sauron's demise at the end of the second age.

From the Silmarillion it appears that Sauron was hewn down by Gil-galad and Elendil, and afterwards the Ring was cut from his dead body's finger by Isildur. Is this the correct order of events? Or was Sauron weakened by Gil-galad and Elendil and then Isildur cut the ring from his living body causing it to be destroyed?

Answer

You're correct; the order of events based on the published texts is unclear.

In Of the Rings of Power and the Third Age we read the following words of Isildur:

This I will have as were-gild for my fathers death, and my brothers. Was it not I that dealt the Enemy his death-blow?

This is absolutely unambiguous; according to this text it was Isildur who killed Sauron. Yet, in the Fellowship of the Ring we read a different story:

It was Gil-galad, Elven-king and Elendil of Westernesse who overthrew Sauron, though they themselves perished in the deed; and Isildur Elendil's son cut the Ring from Sauron's hand and took it for his own.

This suggests that Sauron was killed by Gil-galad and Elendil, and that it was only after that that Isildur cut the Ring off.

Ultimately it seems as though we must accept that this was an event from very ancient history (over 3000 years before the Fellowship formed) and that, while there were people around who remembered it (specifically Elrond, who was there) the event itself is clouded by conflicting accounts.