Have you recently installed AVG? If so, have you run a full scan yet? The first scan after installation is called an "optimized scan". I believe this type of scan is needed to allow the program to function correctly. Everything will be slow until this first scan has finished.
Malwarebytes - Install and update once a week. Run a quick scan after updating and maybe a full scan where time allows.
AVG is a pile of rubbish that repeatedly tells you about its presence. Get MS Security Essentials. It quietly does the job without jumping up in front of your work and stealing the focus so that when you look up you discover you just lost the whole line you just typed.
Moreover, when I had AVG it would tell me that it had updated and I needed to restart the computer even when I was not connected to the Internet. Obviously it could not have updated so what it said was rubbish.