Question.. I'm new to wow but not boxing ...

[Ualaa]

A very basic choice...

a) Tank + 3/4x DPS that can heal, possibly with another class.
b) Tank + 3x DPS + 1x Dedicated healer.

Both approaches have merit, strengths and weaknesses.

Another option, I'm seeing people having success with:
Tank + 2x Healers + 2x DPS.
Especially if the 2x Healers can add some amount of DPS to almost equal a 3rd DPS.
Gunsun has a thread on this composition, with others trying several variants.
2x Holy Pallies, each doing Beacon on 2x Elemental Shammies and then healing 1x Tank, is an example; each heal on the tank, hits the entire group with 1x Heal per other toon and 2x Heal on the tank.

[gunsun]

A very basic choice...

a) Tank + 3/4x DPS that can heal, possibly with another class.
b) Tank + 3x DPS + 1x Dedicated healer.

Both approaches have merit, strengths and weaknesses.

Another option, I'm seeing people having success with:
Tank + 2x Healers + 2x DPS.
Especially if the 2x Healers can add some amount of DPS to almost equal a 3rd DPS.
Gunsun has a thread on this composition, with others trying several variants.
2x Holy Pallies, each doing Beacon on 2x Elemental Shammies and then healing 1x Tank, is an example; each heal on the tank, hits the entire group with 1x Heal per other toon and 2x Heal on the tank.

I did write up a thread on a team that almost plays itself. Shaman are very versatile as primary heals and backup dps. It's the same idea as 4 dps that backup heal, but reversed. You almost never crowd control in the 80-85 instances, which i think is a lot of fun.

I'm not sure if you want to learn that team to start because you have to learn multiple classes and specs. You could run a pally and 4 shaman, and then play with 2 of them as resto shaman. Then you could see if you like it or not.