Choosing the right talents for you is one of the most important things to optimize your healing success. For holy priest there is nothing like a "best talents"; depending on the healing style of a player, everyone will put some points different.
Some other talents aren't optional and every holy priest should have them. Take a look at holy talents to get an overview of the talents.
Talent usage statistics
If you need some help finding your talents, take a look at this page:
http://quickarmory.com/stats/?c=Priest#Holy
It display statistics about which talents are used most and can give you some tips choosing your talents. But keep in mind that the most choosen spec doesnt have to be the best for you.
My current talents
My current build is including Lightwell (great talent, if people in your group understand howto use the lightwell) and I added Healing Focus again, as it is a usefull talent for many encounter in Ulduar.
Builds with empowered renew
Here some builds for priests, casting many renews.
-Healing Focus
-Empowered Renew
-Desperate Prayer
What are the stat caps for the holy/disc priest?
This is my current build http://www.wowhead.com/?talent=bIcbuhbkbZfxt0frqVzV0o. I've recently joined a raiding guild that has no clue on what is or isn't good for a priest. Before I finish my leveling to 80 (1 1/2 levels to go, woot!)
I want to know what are the stats I need to have capped and what are the caps for the stats? Second is my build (see above link), going to be good enough for Naxx at 80 and if not what should I respec to? Forgive my noobness, but this is my main, and rather new to WoW. (2 months game time, 16 days played time for my priest)
Stats/Naxx/Build
There are no caps for the stats for a healing priest, as holy priest you should stack mainly spirit/spellpower/int. If you want get some hasterating too, but in the beginning i would try to concentrate on spirit to get a decent manaregeneration.
For your raiding at naxx you will do fine with arround 1600 sp unbuffed, take some pots so you dont run out of mana, thats it. If you are going to make some normal instances or allready did and have some blue gear you should be ok for naxx.
Naxx non heroic isnt really hard and its more about knowing the bosses then about gear.
Your build isn't bad, but for raiding i would make some little changes. You dont need "Searing Light", as you are not going to make any damage. Maybe get "Holy Concentration" it can help save you some mana. "Surge of Light" is a very nice talent too, take a look at it.