What is a good spyware/malware removal program that is free?

For a virus scanner I am using Avira Antivir and I use adaware sometimes for spyware, but my computer has been lagging something terrible lately. Little random things happen, and I know there has to be some spyware or malware on this bad boy. I don’t want a trial thing, or something that scans it and then tells me I have to pay to remove it. I really need some input, please.

Malware infection, free removal:

Malwarebytes Anti-Malware:

http://www.download.com/Malwarebytes-Anti-Malware/3000-8022_4-10804572.html?hhTest=1.

Select Full Scan.
Remove all infections that it finds after scan.

SUPERAntiSpyware Free Edition:

http://www.download.com/SUPERAntiSpyware-Free-Edition/3000-8022_4-10523889.html

Select Scan your Computer, select your drive and select Perform Complete Scan

Spybot S&D:

http://www.safer-networking.org/en/download/index.html

Download, install, update and Immunize, turn off Tea Timer then click ‘Check for problems’ then when complete select all and then ‘Fix Checked’
Open Spybot, click on Mode, select Advanced, click on Tools then Resident and untick Resident ‘Tea Timer’
Do NOT untick Resident ‘SD Helper’ as that is your protection.

Spyware Doctor Free Basic Edition – Realtime monitoring:

http://pack.google.com

Its free with Google pack, untick all boxes except Spyware Doctor. Download install, update and run.

Get Spyware Doctor For Free

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