When I test the rigid body physics (CTRL A), blender crashes. They should, however, fall straight down indefinitely.
These are all of my active addons.
For what reasons do you suspect it keeps crashing?
These are all of my active addons.
You meant ALT A, right? 
I don’t think that an addon caused the crash. Check your physics settings (again) and how much geometry you have. If your computer isn’t that strong, physics simulations with a lot of geometry are likely to crash.
You may also try to start up blender from the command line. If blender crashes, you will hopefully see there why…