-In VirtualBox 7.0, when you create a new VM and select an ISO, VirtualBox will automatically detect the OS and will not allow you to change it. In VirtualBox 7.1/8.0, when you select an ISO, it should automatically detect the OS, BUT you can change it if it doesn't select the right OS.
-In VirtualBox 7.0, if you shutdown a VM with the date modified, it will not save those changes. If you start it back up, it will reset back to the current date. In VirtualBox 7.1/8.0, it should keep those changes whether you're restarting or shutting down.