I am by no means an expert, but I'll offer you what I know.
Your hp is possibly a tiny bit low, but with raid buffs you'll be close to 30k which should be fine for OT. Might want it to be a little higher for MT.
You're def capped which obviously is huge.
The only thing that scares me is you avoidance is very low. DK's are avoidance tanks, so that's a stat that we need to survive. (See below)
That spec will not under any circumstances work for tanking. You're missing all the dodge and parry talents as well as toughness. Get your spec worked out and you'll be fine to OT naxx for sure, although MT you may come up a little short on hp.
I'm new here, so by all means if anyone can correct me do so. I'm still learning myself.