I'd allmost suggest to stop playing with more accounts and play with 1 char first. WoW has sooo much to offer as a game, wich you can do ofcourse with your own party, but playing with real people really helps, specially when new. You won't regret it ... WoW is alot bigger then you might think...

To answer your question: Shamans are a class you can use for allmost everything, healing ? Np! Tanking ? Np! Insane dps? Np Buff your party with totttummmsss? Np!

Paladins, druids and shamans are the most used classes, and mages and locks for dps. Ofcourse you can roll with any thing you like, but take in mind a melee class needs to be in range. Can be done but just more work...

PS: Welcome to the forums and WoW :thumbsup: