According class choice:
If you are looking for a well armored damage dealer probably
Fury warrior, retribution pala or shaman.
Consider though, that in WoW you will need to adapt to your calsses team job to be taken into dungeons.
Like warrior is supposed to tank NOT make damage. And palas either tank or heal mostly.
Top tier damage dealers are mages and probably warlocks.
Maybe the best is to start with a druid or paladin. Those two can take any of the 3 roles: damage, tanking, healing.