On my old PC I have Norton Security Suite, SuperAntiSpyware-free, MalwareBytes-Free and CCCleaner, I find they work great in removing spyware, malware and virus's. You can also run the scan online inspector at Secunia (free) (Scan Online with Seconia OSI) and it will check your system to make sure everything in your system is up to date and it checks for vulnerabilities.