I think most Guests will be like you and will be getting up at 4:30 AM for SWGE.
It's not the whole park, but most of it. All the rides should be running, but I don't believe some of the shows will start that early.
Their site says:
Agreed - I don't see a mad rush at 6am for TSL or the other parts of the park. I think if you're getting up at 4:30am (like I plan to 2 days of our trip) you're going for SW:GE. I also think the majority of guests heading to TSL have little ones and aren't leaving the hotel at 4:30am...now, I'm a terrible parent and I AM pulling elementary aged kids and 65 year old in-laws out the door at 4:30am but they know that's how I roll at WDW.
