World Of Warcraft Question?

Nope! Once you install Wrath of the Lich King and Cataclysm, your world will update and everything will be available to you. You simply have to go to those areas. Now, as I'm sure you know, you won't be able to go fight the Lich King or anything like that immediately as you will need to gear up and get into a raid for that. And it also sounds like you're just getting back into the game, so I hope you have fun and welcome back to WoW!