scanning for viruses is normally very lengthy process.It takes about an hour or thirty minutes to scan your pc from viruses & trojans & spywares.Here is a website that enables you to scan your pc in seconds.Its called NanoScan.It is a project of Panda Security.You only have to go to the site & press the "NanoScan My PC" button.It Detects more than 2,720,432 Viruses,trojans & spywares.
Here is a screenshot of the scan result of my pc.And it shows that my Pc was scanned in 66 seconds.So you can also scan your pc within seconds at Nanoscan.