I'd say to go with:
Special Walls:
Tyranitar ~ 252HP/216SDef Careful. Counters the Special Threats BEST IMO. It destroys Lati, Electrics, Rotoms, Psychics, etc.
OR
Snorlax ~ Standard....I suppose this could counter Electrics, etc. but over Tyranitar,it's best quality would have to be beating...