Upgrade Ubuntu 16.04 LTS to 18.04 LTS = 5 desktop environments

I’m testing Ubuntu 16.04 LTS with Unity to 18.04 LTS upgrade. After rebooting The first thing I notice is five different desktop environments available at sign in:

• I assume the first option is GNOME on Wayland???
• The first and second options result in a movable mouse cursor in a sea of purple.
• The third option “Ubuntu” I have no idea if it is supposed to be Wayland or Xorg. Selecting it results in a movable mouse pointer in a sea of purple.
• The fourth option I wasn’t brave enough to select due to Wayland problems I’ve read about.
• The last option “Unity” works OK but not what I would call ready for prime-time.

Can anyone explain what option 1 “GNOME” and option 3 “Ubuntu” are supposed to be using for Desktop Environment (DE)?

As I’m running the test in an easily duplicated environment: Bash script to clone Ubuntu to new partition for testing 18.04 LTS upgrade, is there something I can do before conversion rather than fixing after conversion? If so I can modify the cloning script to possibly speed up conversion and one less thing to do after conversion.

I would first click the gear to select the Desktop environment and then enter my password. Then the software says “Invalid Password”. I retype my password and click the gear icon again to discover my first choice has reset to the default and I have to select my first choice again. The second time I enter my password it is accepted. This happens on all options I tried except for “Unity” which accepted my password the first time.