Keep the spybot in your machine. It is good. Replace AVG antivirus with Bitdefender or Avast (freeversion). Both are good to use.
Note: Its recommended to run only one anti-virus application at a time. Using more than two anti-virua application at a time will not help you any way. Even if you have to run more than one antivirus application, please disable the existing antivirus application and run the other AV which you want to.
You can delete delete all the temporary files and cookies using a freeware application "CCleaner".
To download CCleaner please proceed to the following link:
Please reply back if you need more clarification and help.
Thank you :)