download the anti spyware and anti malware software from the internet and scan the computer in safe mode.
installed the only one anti virus software in the computer . remove all the other anti virus software from the computer . because more than one anti virus software will decrease the performance of the computer.
so use the AVG anti virus software or the AVAST anti virus software in the computer.
update the anti virus software and scan the computer .delete all the detected threats from the computer.
delete temp , prefetch files from the computer these are unwanted files so delete it.
download the anti malware from the internet and scan the computer in safe mode.
before scanning the create a restore point and take the back up of the registry .
for further assistance you can approach at this source at
http://www.iyogi.co.uk/spyware-support.html