Avast Anti virus - Protects your PC from security attacks.

Believe it or not, for MOST  users, this is sufficient protection, and the price is right!

Download it here: https://www.avast.com/

SyncBack- Use this program to keep your data synchronized and backed up.

Download it here: https://www.2brightsparks.com/download-syncback.html

HiJack This! - Use this program to analyze system files for tampering. BE CAREFUL!

This tool is NOT for the timid!

Download it here: https://sourceforge.net/projects/hjt/

Handbrake - The Open Source Video Transcoder.

Download it here: https://handbrake.fr/downloads.php