WotLK Best PvE spec Naxx

[Miraval92]

Hi guys, i was wondering what is the most performing pve spec for Frostmourne server. Atm we are at Naxx so with these low stats i dont know if i should go frostfire,arcanefire or just arcane to maximize my dps. Now i'm using fire with some talents in arcane to get the focus magic but i'm too low in raid dps.
Can u help me a little? aaaand sorry for the bad english

[Griseggra]

At low gs idd say arcane. Dont take slow or arcane barrage. Pick icy veins from frost

[suxus]

https://ibb.co/GFrFkRF

Take these talents from now. There is still 1 talent left to spend. Spend it on either Arcane Focus if you need extra hit, Mind Mastery, or even Arcane Stability if you gonna do more 10 man content. Once you gear yourself, put 2/2 Arcane Subtlety and later you can remove Magic Absorption, depending how much your raid struggles. Utilize Incanter's absorption as much as you can. You can even remove one more point from Mind Mastery if you're low on intellect and put it on extra hit, depending on your gear and stats.