WoW: Classic is scheduled for August 27 (technically August 26 if you're in the Americas). The soonest that you can play it is starting in May, during Blizzard's scheduled stress tests. To opt-in you must have an active subscription on your Battle.net account. If you do, go to Account Management and select the Wow Classic beta. Keep in mind, there will be level caps during the test. The schedule is as follows:
Before we give you the Classic WoW Best Leveling Class, let’s discuss what we consider to be the Best Classes to choose for levelling. These are ranked based on how fast and easy it is to level up from 1 – 60 whether you are doing it with a group or simply Solo levelling yourself. Classes with AOE Damage and the ability to self heal tend to rank higher simply because it’s much easier to level up when you can sustain your health and clear mobs of monsters. In the case of Warlock and Hunter Class you have a pet that can help tank mobs while you DPS them down, this is another huge benefit when leveling up.