With AVG Internet Security there is a Link Scanner that sends a simulated IE or Mozilla browser request to load the first page of any site when you search Google for something. So... if you have 50 sites loading up when a search is initiated, you'll wait a minute or two if AVG's Link Scanner is active.

You can read a news article here.

Here's my method for disabling the Link Scanner:

  1- Launch the program;
  2- In the Security Componenents & Status Overview (click the Overview tab), double-click Link Scanner;
  3- Uncheck all the boxes, then Save Changes;
  4- Click the Overview tab, then right-click Link Scanner and select Ignore Component State

Google will load a list of sites without checking them, and you also won't see an error message that AVG isn't configured properly.