Python 3.5.2-bit install SNAFU

[sparkz_alot]

I checked the system path, and found references to Python 2.7 but none to 3.5

 I would leave this alone.  As to the others, 1 & 4 can definitely be removed. The other two, well they refer to the file locations referenced. These are files MS records when you install a program and is used for updates and uninstalling. If you delete them, the program will still work, but you will get an error if you try uninstalling the program. In File Explorer, if you look for this entry
" C:\Users\<account>\AppData\Roaming\Microsoft\Installer\{xxx}\" and it's there, you can click on it and get an idea of what it's for. If it's not there, it's an unused entry and can be removed.

Larz60+ also has a good idea. I will add to his suggestion of Bleachbit, CCleaner and Auslogics Registry Cleaner. Note that the first two analyze the file system and registry, Auslogics only analyzes the registry. Not surprisingly all three will come up with different results, so I use two of them. All three operate in what I'll call "safe" mode. They report only what they determine is safe to delete and therefore may not report all instances. All three have the option to "backup" before deleting and I would suggest doing that, especially if you've never used the product before. I've never had to restore after cleaning, but better safe than sorry right? Both Bleachbit and CCleaner claim no adware, spyware, malware, browser toolbars, or "value-added software. Auslogics will try and install it's Boostspeed, but you can uncheck that option.  If you go this route, run the program(s) then try your searches again and see what you come up with.