I have spyware or trojan viruses on my laptop, should I re-install my laptop completely?

I have had some spyware and trojans all over my hard drive lately. The following spywares are named, Smitfraud-C & Win32.BHO.sx. I have four Anti-Spyware softwares: ThreatFire, Avast!, SUPERAntiSpyware, and SpyBot. I used all 4 of them, and they say there are no malicious threats left, but I want to re-install my laptop just to be safe. Would that help? Thanks.
My laptop is a Windows Vista Home Basic 32.

To Remove Smitfraud-C & Win32.BHO.sx in you Computer. Restart you Computer Safe Mode with Networking Press here http://www.computerhope.com/issues/chsafe.htm#02

in the Safe Mode with Networking Download and Scan By Using Malwarebytes’ Anti-Malware http://www.download.com/Malwarebytes-Anti-Malware/3000-8022_4-10804572.html?tag=contentBody;mostPopTwoColWrap&cdlPid=10997763

Download and Scan By using Norman Malware Cleaner Press here http://majorgeeks.com/downloadget.php?id=5450&file=1&evp=6980e63d4e482f0670e991265b3250e7

Download and Scan By Using SmitFraudFix Press here http://siri.geekstogo.com/SmitfraudFix.php

After Finish Remove Smitfraud-C & Win32.BHO.sx Restart you Computer To Be Normal.

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