I guess so, but I'm using AVG Free antivirus myself. You can also try the free anti-virus software from Microsoft -> Microsoft Security Essentials.
Windows Starter Kit - Download.com Security Starter Kit - Download.com Utilities Starter Kit - Download.com flash plugin, pdf reader, anti virus, spyware scanner, system defragmenter, system backup, winzip ,GIMP, depends wat you really do and need
I had used AVG premium antivirus and it gaves me satisfactory result. Why not to go with premium when the free antivirus program can't able to scan the system properly. Quick heal is also an availeable option which is free but more effective then any other antivirus.
