Where do you find the proper "install.exe" to use? How do you know it's the one you want? How do you set it up? How do you know it's not a crapware/malware/what

Where do you find the proper "install.exe" to use? How do you know it's the one you want? How do you set it up? How do you know it's not a crapware/malware/whatever? How do you know it's up and running? How do you prevent your children from disabling it? ...