What metal CDs do Ineed?

I'm trying to get into metal, because, apparently, my favorite band isn't metal despite everything I've read about them.

Currently my favorite metal bands are Bring Me The Horizon, System Of a Down, Thornhill, Trivium, and Black Sabbath. Of these bands I pretty only listen to the first two.

My general taste is grunge bands like Alice in Chains, Nirvana, Pearl Jam, Hole, and Soundgarden.

What are essential metal CDs that everyone needs? I'm tired of feeling so much like a pussy for not being into metal and it needs to change.