Sorry to be a fence-sitter (not a comfortable position at the best of times!) but I really can't pick just one!
My Nikon F80 generally wears a Nikkor 28-105mm D, but this can be pretty much anywhere on its range. It even spends some time as a 1:2 semi-macro.
Landscapes (usually) tend towards the wider end of the range, portraits (usually) tend towards the longer. Unless I change my mind. In which case the opposite may apply. Or not.
There, I hope that's cleared the matter up once and for all!