Look inside:Onecare scanner

When it comes to online anti virus scanners,I prefer Windows Live OneCare Scanner . It not only fixes viruses but removes junk from your hard disk and Improves your PC's performance by tuning and cleaning it up .
While scanning,you can select to make a complete(Full Service) scan or Separate scan for clean and tune up.
If you found a IE 7 Script Error preventing Scanner from running , then follow under given process

Try going to regedit (type "regedit" in Run and then
press enter) and look for the following key:

[HKEY_CURRENT_USER\Software\Microsoft\Internet
Explorer\Main\FeatureControl\
FEATURE_LOCALMACHINE_LOCKDOWN]
"iexplore.exe"=dword:00000000

You can either delete it or set the value to 1, WL oncare team
founds that both work.

The "Full Scan" scans for viruses (comprehensive scan or quick scan), hard disk performance (Disk fragmentation scan and/or Desk cleanup scan) and network safety (open port scan). The "Quick Scan" only scans for viruses, only on specific areas on the computer
You can also have it downloaded in your PC , trial version for 90 days,Or full subscription (protection and maintenance for up to 3 PCs )for $49.95 a year. The Version 2 has more features such as multi-PC and home network management, printer sharing support, start-time optimizer, proactive fixes and recommendations, monthly reports, centralized backup, and online photo backup.
It also does Disk defragmentation on your PC
It sticks on notification area of taskbar and tells about status of the system's health by using three alert colors: green (good), yellow (fair), and red (at risk).
Hope you get a green one :-)