Windows Defender highlights:
- Provides robust protection from most types of malware
- Has a built-in firewall
- Phishing protection for IE and Edge browsers
- Parental control feature is available.
- Comes pre-installed in Windows OS; protection is enabled by default.
Ad-Aware highlights:
- Offers a free baseline real-time monitoring antivirus
- Compatible with Windows 7 and higher
- Requires less than 1% of CPU to perform the scans
- Users can install other antiviruses along with Adaware if they choose the compatible mode
- Monitors registry to spot modifications
- Detects and blocks malware before it has any chance to run
- Offers a sandbox to run infected files without any harm to the system