I'd definitely put the FFVII and FFVIII soundtracks on that list for me for a start, after that it was hearing Alice Cooper and Metallica for the first time which opened my eyes and ears to the world of Heavy Metal I'm neck deep in today.
Seeing Iron Maiden live for the first time was a major moment as well but the standouts are discovering Judas Priest, Motorhead and Saxon which still today are the very core of my music tastes. I've seen Priest 2 times, Motorhead 4 times before the great Lemmy himself passed on but seeing Motorhead is what really made me want to keep trying and stick with bass guitar. I've seen Saxon about 5 times now and I've met all/most of the band even. They're definitely one of my absolute favourites and primary influences, inspirations for my own musical ambitions and endeavours.

A huge moment was seeing Ronnie James Dio live with Black Sabbath as that was a monster of a show! Now, didn't cost much and compared to the prices Ozzy + Sabbath is charging to see their farewell shows I think I was witness to an absolute privilege and honour!

I've seen a fair few legendary status metal bands too, Satan, Mythra, Raven, Anvil, Tysondog, Blitzkrieg. Absolute class acts every one of them.