Moving this to the New Multi-Boxers & Support section (where it should have been posted in the first place *cough*)

Personally, I wouldn't base class choice on classes that start in the same zone, since it's fairly easy to get lowbies from one starting zone to another (or even do the first few levels separately, and have them meet up at a common city). That being said, a tank / healer combo works well for dual boxers. I'd probably go a Pally & Shammy myself becuase of the nice combo of totems and auras...

Addons can normally be enabled or disabled at the character selection screen.

Cheers,
Stealthy