Watchman is the tool of choice for restraining access to applications and documents, and stopping users from messing around.
ScreenLock is a nice, trial version program only available for Windows, that is part of the category Security software with subcategory Blockers & Access Control (more specifically Boot).
SafeDNS protects you from inappropriate websites.
Public Access Desktop
If your PC is shared by many people, then you don't know what's happening to it when you're not there.
Lock your laptop automatically when you close the lid in Windows 10.
HideBox was developed to make possible, even for novice users, to hide folders containing personal or private data.
FrontFace Lockdown Tool
Protect and lock down any Windows PC for use as public kiosk terminal or for digital signage applications!.
Folder Latch is an amazing, free program only available for Windows, that is part of the category Security software with subcategory Blockers & Access Control (more specifically Files & Folders).
BossKey is a simple virtual desktop program.
Ad Blocker PRO
Block website, and unwanted websites from being seen as adverts and via popup adverts too, includes blocking known hacker, virus and other malware websites, advert servers, tracking and more!.
Directory Monitor is a free software that allows you to monitor the files in the directories on your computer.