The two rides at Galaxy’s Edge are Millennium Falcon: Smuggler’s Run and Rise of the Resistance. Some more info here.
I’m primarily looking forward to Rise of the Resistance because I love me a dark ride and I’m incredibly interested in seeing the latest tech and animatronics. Unfortunately, Rise of the Resistance isn’t finished yet and won’t be opening along with the land this week but the initial reviews for Smmugler’s Run have been very positive.
Currently guests are limited to only 4 hours in the park and a reservation is required. Even with these measures the crowds will probably still be miserable. I’ve heard 3 hours just to create a light saber and 2 hours Smuggler’s Run.