1. Crisis on Infinite Earths
I hate Multiverse so a crisis that unify everything to one Universe and one Earth is my story. And it was a great one, epic too.
2. Zero Hour
The story itself is mediocre but his epilogue started the period of DC I loved the most.
I loved some Zero Hour issues like Robin#0, Tim Drake teaming-up with a young Dick Grayson Robin it's one of my favorite comic af all time.
3. Infinite Crisis
The story is fine altough I'll never forgive Johns for using some characters as cannon fodder only for the sake of shock value.
Final Crisis, Metal and Death Metal are not my cup of tea. Too much pretentious and complex. I'm not a fan of both Morrison and Snyder.
Identity Crisis and Heores in Crisis are really bad. The only hope is to forget about it.
Convergence is the most useless and disappoitning event I've ever read.
Flashpoint, I can't remember almost anything about it. All I know is that after this event DC continuity stopped making sense forever, and most of the characters I used to love are slaughtered for good.