I would love to see Metallica but that is a stretch, so here is my dream list.

main stage
6) Stone Sour
5) Megadeth
4) Slayer
3) Lamb Of God
2) Iron Maiden/Van Halen/Metallica
1) Black Sabbath
second stage
White Chapel
August Burns Red
Misfits
Down
Killswitch Engage
Hatebreed
Suicidal Tendencies
Sevendust