If you wish to continue using Wrath of the Lich King, then yes you have to buy the full package and upgrade your current account. If not, your account should simply be playable but without any WotLK features.
Yes you have to download the whole game and its patches before you can upgrade to the Burning Crusade.
buy The Burning Crusade Expansion Package,The Wrath of the Lich King Expansion,...
Burning Crusade (and Wrath of the Lich King) is an expansion pack to World of Warcraft. When you upgrade to Burning Crusade/Wrath of the Lich King, you are actually upgrading your account, not the software. The client is automatically updated when expansions come out.
If you upgrade from basic wow, to Burning Crusade, yes, you get a free month. Same goes for if you upgrade from Burning Crusade to Wrath of the Lich King.
The Burning Crusade upgrade allows you to experience the mystery and doom of Illidan's Outland, in other words it lets you play in the new world, called The Outlands.
In order to make a Draeni character, you must have the Burning Crusade or later account upgrade. That will allow you to make Draeni as well as Blood Elf characters.
You only have to upgrade if you want to level higher and access the content of the expansions. Burning Crusade - up to 70, The Outlands Wrath of the Lich King - up to 80, northrend Cataclsym - up to 85, cataclysm content
Yes. As with all previous expansions, you must have the expansion before in order to upgrade to the current expansion. IE: you need Vanilla WoW, Burning Crusade, and Wrath of the Lich King on your account in order for you to upgrade to Cataclysm.
Blizzard recently changed it to where "The Burning Crusade" is now included in new accounts, and all vanilla (original game) accounts were automatically upgraded to BC accounts. So no, you do not have to buy them separately.
If your WoW account got banned and it is permanent then you will need to buy a completely new account from a retailer like walmart or bestbuy and if you wish to have The Burning Crusade enabled on the account you will have to upgrade it which can be done online now I beleive. But you will need to upgrade the account again. In addition: you also have to purchase a new burning crusade key
There is only one World of Warcraft game. It has a few expansions though. You should start out with the vanilla (the original game) wow, and decide if you like it. Then you can add each expansion in order, Burning Crusade, Wrath of the Lich King, and finally Cataclysm. You need to add each in order though, as each gives you access to new levels and content. If you want to play cataclysm content, then you need to first upgrade your account to Burning Crusade and then upgrade to Wrath of the Lich King, and finally Cataclysm.
Nope you will need the burning crusade expansion installed before it will allow you to install WotLK.