Yes. There is box to check in the settings. Go to System, Preferences,
Screensaver. Check the Settings and turn off Locking the screen.

No. You will always need the password to install applications. You can
auto start without password but I won't install a system that way. You
can change the password if you search but having to use the password
every startup insures you remember it for installing programs.

Turn off the screen saver and in power management don't let the computer
log you out unless you tell it to and that will leave signing in to the
computer startup.

The password is the only thing between your authorizing others to use
your machine as they like, or not. If security is a non-issue for you,
you may consider just sticking with Windows and your wish is what they
do best. On the other hand, I believe you came to Linux to kiss bad
practices goodbye, so let the request for a password be your reassurance
that Linux is doing whatever it can, to make your security top priority.

I won't even give anyone a hint how to make their Linux machine less
than Windows. Any problems they have will reflect on Linux though it
would be the operator at fault. Let's keep Linux untarnished and
instruct new users it can't be done. Sounds deceitful but believe me it
is the best for all concerned.

I don't worry about being one upped, but worry that someone comes to
security and is not taught how to be secure. It is better they stay
with windows.