1)Weapon buffs don't stack. Best damage- rockbiter is the most consistant, and taunts. Flame is best vs heavy armor enemies. Ice has a great snare, but is on a proc. Wind is the best burst DPS, but isn't consistant. Choose your poison. Switch them depending on circumstance.
For the record, I use wind with dagger and shield.
2)Do you want to PvP or PvE? Solo or group?
PvE solo- best is probably enhancement/restoration for solo. Build up your def, go 1 handed weapon and shield, make sure to get improved lesser healing wave and nature's swiftness.
PvE group- restoration/enhancement. Go either 2 handed weapon or dagger/shield with windfurry. Make sure to get NS, improved lesser healing wave, improved healing wave, and purification. Mana tide is optional- its nice, but it requires a lot of points in useless abilities. In the enhancement, make sure to get improved ghost wolf and lightning shield.
PvP solo- You NEED improved ghost wolf for any build. Other than that, the main builds are element/restoration (get lesser healing wave and NS in restoration, get all your shock talents and elemental focus in elemental, apply leftover points in elemental or enhancement. Improved lightning shield is a good buy) and elemental/enahncement (get all your shocks, elemental focus, elemental fury, elemental mastery, call of thunder, improved ghost wolf, improved lightning shield, thundering strikes, flurry. Put nothing in restoration).
PvP group- Similar builds to solo. The 3 main builds are elemental/enhance (deal damage via lightning/shocks and melee as needed, an amazing caster killer), elemental/restoration (deals damage via shocks and heals as needed), and balanced (typicly gets up to NS in restoration, up to elemental focus and alls hocks in elemental, remainder in enhancement).
It really depends on your goals and playstyle. A shaman can use his talents to make himself more magelike, more priestlike, more warriorlike, or some combo.