If you want a rusher, sorc is a bad idea, too many elemental immunes. Go with someone that does magical damage, like a bone Necro or Hammerdin (my choice) They will be able to kill anything, and will live longer then a sorc.
EDIT:
If you are dead set on sorc, go cold sorc.
Bliz - higher damage, but stationary skill
Orb - less damage but you can hit everything in a path
I also suggest a prayer merc with Insight, for mana and life regen. Or if you got some wealth go for Obedience weapon.
Up to you.