Indeed it was Hetfield,
but he was singing 'Seasons in the Sun'
(
helmetcream,
Tue 14 May 2002, 18:58,
archived)
It was definitely pre-Betallica though
They've sold out now turning themselves into a cover band.
(
Professor Fnord Regius Professor of B3ta Chronology,
Tue 14 May 2002, 18:59,
archived)