Spyware viruses--how to get rid of it

Depends on the type of malware. It's a huge topic.

Best way is to avoid browsing/clicking unknown links, downloading from unknown torrent sites/cracks and keygens, scan the pendrive if its from your friend.

Be sure to update all of your Anti-Spyware programs, then do a thorough scan with each. And, update your Antivirus program and do a thorough scan with that also. You may have to go to your antivirus software provider and find a specific Spyware cleaner for that specific spyware. Sometimes the tough ones need it.

Just the free one does the job.
Malwarebytes : Malwarebytes Anti-Malware PRO removes malware including viruses, spyware, worms and trojans, plus it protects your computer (http://www.malwarebytes.org/products/malwarebytes_free)

Some instructions if you need them: How to use Malwarebytes' Anti-Malware to scan and remove malware from your computer (http://www.bleepingcomputer.com/virus-removal/how-to-use-malwarebytes-anti-malware-tutorial)