Which should I use?

So I'm pretty new to this tanking thing. I need some help with deciding which gear to use. I'm def 522, health is 2.5k unbuffed, exp is 20, and my dodge is 18.99% while my parry is 11.04%.
First question, what should I be targeting as of now.
Second, I'm trying to decide between Sollerets of suffering drops from FOS, and Boots of Heartfelt Repentance drops from TOC.

Thanks for the help.

Get 540 defense so you are uncrittable by raid bosses (you only need 535 is you are only doing heroics).

2.5k health? :eek: .... :rolleyes: