Guild Wars 2

it says that in when you get the game that it comes with the original game as well, so i am wondering if the two games come as separate keys? and if so can i register the main game to a new account and HOT to this one

It comes as a single serial key, so no you wont be able to do that.

When purchasing (or pre-purchasing) Heart of Thorns, you receive a Serial Key. You have two options:

Create a new account that can access the core game, as well as Heart of Thorns (once released)

or

Upgrade an existing account that will be able to access Heart of Thorns (once released)

Good luck.