Microsoft Security Essential:
Don’t be fooled by numerous free and paid software for enabling virus security on your PC. Simply install Microsoft Security Essential for free and run a full scan. This free software will prevent your PC from all the potential threats without costing a single penny. The software doesn’t use much resources and hence doesn’t interfere with the performance. There are three scans – quick, custom and full. You can also schedule a weekly full automatic scan when the PC is not being used.