Pally should be pretty easy to macro/tank with.
Mash your 96969 macro.
Just need to worry about facing/positioning.

You can either Kings the mages and go with a Mana Spring/Mana Tide on the shaman.
Or Wisdom the mages, and go with Healing Stream for passive heals on the shaman.

Chances are, the mages will be parked with the shaman.
So Chain heal will be fine for healing through AoE crap.
And you can Healing Wave or L.HW the pally, or Riptide too.

You have good stacking dps from the mages.
CC is you ever need it, but have not needed it in WotLK yet.

Shammies are excellent boxed healers.
Totems are nice buffs, Bloodlust/Heroism is nice too.

Two rezzers on the team.
And the shaman can Ankh for wipe recovery.
Or the pally can Divine Intervention the shaman too.