i meant transition blindside up a couple posts my bad
but... heres the deal.
you probably want at least 8" of travel.
for your rear shock you want a dhx 5.0, thats the only real option here, for forks, marzocchi, fox and rockshox all make good forks.
the rockshox boxxer is a good dh fork, you can get the team for fairly cheap, theyre fairly light, and pretty durable.
marzocchi stuff tends to be a bit, tougher and heavier, and definitely doesnt ride as nice.
fox is basically the best of the best, but theyre shits expensive.
for frames, kona is total balls, transition is good, giant is good, intense is very good (but i dont think you want to pay that much) specialized is alright, new trek stuff is pretty decent. iron horse doesnt make downhill bike anymore.
khs actually has a very good frame, they seem like a bit of an off brand, but theyre frame is identical to my diamondback, that i raced before i got hurt which was a phenomonal bike.