Flap 40, autobrake 3. Don't muck about on short(ish) runways - especially in the -800!
Flap 40 is preferable as the additional drag places the aircraft into a more stable part of the L/D curve and requires higher N1 and therefore much better engine response. The -800 is very unstable in speed at flap 30 at about Vref+5, and worse at +15 or so. I seldom land flap 30, and only when there's a reasonable amount of runway and a decently stable day. Of course, in strong winds, flap 30 is necessary to avoid problems with flap load relief.
The flap system is much more susceptible to wear at high speeds than low - hence it's wise to select each stage at maneuvering speed plus 10 or less, and never near the limit (unless you want, in a few years time, to really get up close and personal with the flap non-normals!)