For Grass, I used a team of Lilligant/Leafeon/Ferrothorn. Even without a functional Leech Seed which mine has, Ferro can wall almost anything you will face in the Grass Type Expert tournament and destroy them with Gyro Ball. My Leafeon has X-Scissor and Swords Dance and he did his share of work with those. Lilligant was a backup plan vs. special attackers but I didn't end up needing her all 3 battles.
I think for Poison it was Scolipede/Gengar/Drapion. Two of those have Quake and I don't remember having any difficulty in this one.
Ice was Cloyster/Beartic/Froslass. Cloyster has Shell Smash and Rock Blast and went through 3 teams like a hot knife through butter. The one time Rock Blast missed, the opponent's pokemon used a non-damaging move anyway. --- Pokemon Black 1: 2150 9067 9370, Black 2: 1507 3551 4929