Best Opener I've Seen:
Moonchild by Iron Maiden. SSoaSS is one of my favorite albums (and is what got me into Maiden in the first place), so hearing it live was killer.
Opener I Want to See:
Dopesmoker by Sleep (even if it's just a fragment of it). Enough said.
Best Closer I've Seen:
A tie between Five Year Plan by DRI and Pussy by Rammstein. The former came at the right time when everyone was tired, but they still got together for one last pit; the latter was just goddamn hilarious for the show, especially with the dick cannon.
Closer I Want to See:
Solitude by Candlemass, especially if it follows At the Gallows End.