Well if you want to do 5-man instances in Outlands I'd say you def. need a dedicated tank and healer (at least at your level range).
What tank you go for is really up to you but a pally is a lot easier then a druid and having access to blessings does more for group synergy as well.

I don't recall if the hp quest rewards do offer any sort of tanking gear but getting your stamina up should be your first priority. If you're using any treat meter like omen it should be easy enough to not over-aggro with your druids.

I also recommend (since you haven't run a dedicated tank/healer group) to practice your macros in a lower lvl instance such as Strat e.g.