Full HD (1080p) if you are planning to take HD settop box. While if the content is SD then HD ready (720p) is sufficient.
Also the other thing to note is size of screen. If you take big size TV the SD content look blurry and soft, also even HD content might look blurry. So make sure size of screen not go beyond 43 inch if HD and if SD content then not beyond 32 inch.
Anyway I personally think 32 inch is ideal for 1080p HD content especially if planning to watch SD contents too. 43 inch and up to 55 inch for 4K HD to make sure video not get soft.
Concerning TV brands Sony is best and next is LG. Sony usually not require any colour calibration while other brands require it and not sure if able to change settings like in computer.