Sorry, you've reported a range of issues here and it's not clear what the problem is.

Many many people (literally millions) have successfully installed Python on Windows with these installers, and even more (including most Microsoft products) use the installer toolkit that we use. Fundamentally, it works correctly. Most issues are due to problems or configuration settings on the target machine.

The installer file registration is handled by Windows, and is not ours to manage. If the OS is choosing to leave them there after removing the files, you'll have to report it to them.

Perhaps you could reproduce the issue, and then send all the Python log files from your %TEMP% directory? That should show us why your install is failing.