It seems you are using the older version of AVG PC TuneUp. You can find changes in the Rescue Center (and revert them, if you are not satisfied with the outcome). Please see this FAQ article (the second part dedicated to the older PC TuneUp).
If you wish to upgrade to the newer AVG PC TuneUp (for free), please upgrade your license number using this web page and then download&install the most recent AVG PC TuneUp. We recommend uninstalling the older AVG PC TuneUp prior installing the new version.
I'm using AVG free version that I just downloaded and was having a gander and came across 'System Advisor', So, I clicked it and it gave me a list of things to disable to make my computer more fast. I went ahead and disabled what was recommended. I disable something to do with the graphics I think because now the graphics just seem very basic. I'm using window 7 ultimate. How can I view or find what I disabled? Thank you!