Lavasoft Ad-Aware is a free utility for personal and Home users which now includes an Anti-virus engine. too.
The features are
Comprehensive Anti-Malware Detection – A power-packed combination of our pioneer anti-spyware technology together with traditional anti-virus to provide comprehensive malware protection, including protection against virus, spyware, blended malware, trojans, rootkits, hijackers, keyloggers, and much more.
Ad-Watch Live! Basic – Integrated real-time process protection blocks malicious processes and infected programs that try to start or run on your system, to prevent them from further integration in your system.
Genotype Detection Technology
Behavior-Based Heuristics Detection
Rootkit Removal System
The Neutralizer – Advanced removal tool combats malware that attempts to restore itself even after rebooting your system.
Download Guard for Internet Explorer
Detect, Remove and Repair
Easy to install and Use
External Drive Scanning