Here are some helpful video guides I put together covering each boss of the starting zone dungeons. I try to be as informative as possible so forgive me if I leave anything out.
Group Setup: 1 Tank(me), 2 DPS, 1 Healer.
My Skill Bar: Ransack,
Igneous Shield,
Razor Armor,
Choking Talons,
Immovable(sometimes
Defensive Posture for extra block mitigation)
Tanking Mindset: Whenever I engage a group of mobs I pop
Razor Armor for the defensive buff and then I use
Choking Talons to immobilize and reduce enemy weapon damage. The immobilize helps the DPS focus down targets because they are stuck in one place, and the reduced weapon damage helps out with defenses for the whole group. After that I use
Ransack to taunt as many enemies as possible and the skill also gives me armor for each hit.
Igneous Shield and
Immovable are skills I use when I need to soak up more damage, but these are entirely optional. Sometimes I use
Defensive Posture instead of Immovable for the extra block mitigation. You can also replace
Igneous Shield with a DPS move. I like to use
Searing Strike as a replacement because it has a low magicka cost and also does DOT.
Also, as a tank make sure you pay attention to your stamina bar. Blocking, dodging and using ransack are key to being an effective tank so make sure you have enough stamina at all times to use one of these maneuvers. Eating food that buffs stamina will help out a lot here and stamina potions as well.
Spindleclutch: Recommended Group Setup: Starting groups will definitely require a Tank + 2 DPS + Healer type of group. For more experienced players and teammates you can possibly complete Spindleclutch without a dedicated tank as long as you can avoid red aoe circles and block attacks effectively. The last boss will kick your ass if you can't dodge red aoe circles so if you think your skilled enough go right ahead.
The Banished Cells:Recommended Group Setup: Tank + 2 DPS + Healer is your best bet for survival here in my opinion. There are several bosses that do a lot of damage and also a boss that sucks life very quickly so a Healer will definitely be needed.
Fungal Grotto:Recommended Group Setup: Tank + 2 DPS + Healer is the safest group for this dungeon. For experienced players and teammates it is possible to complete this dungeon with an off tank or off heals. There aren't a lot of high damage mobs in Fungal Grotto so if your competent with avoiding and blocking most attacks then your group should be fine with an off healer/off tank.