Prevent

Prevent is a tiny and easy-to-use program which allows you to disable some basic functions of Windows, such as cut, copy, paste and delete.
This type of software can come in handy if you share your computer with people who you don't want to modify your data, such as children.
The interface of the application is based on a standard window with an uncomplicated layout. So, all you have to do is define a global keyboard shorcut, in order to disable Prevent.
Enabling it can only be done by running its executable file. When the app is enabled, the context menu items are greyed out and Task Manager is deactivated. However, there seems to be some compatibility issues with Windows 7.
For example, we have successfully opened Task Manager while Prevent was active. Also, we are able to delete text within word processors.
The program runs on a very low amount of CPU and system memory, so it doesn't make an impact on the computer's performance. Plus, it has a good response time. Unfortunately, we have managed to bypass the app's restrictions during our tests. But we must keep in mind the fact that Prevent has never been updated.