Sometimes a strange problem occurs that do not let you open any other website but Google websites only. I had faced this problem and I always thought that there is an outage but when it started to happen very often I had to research and I found that it was due to wrong MTU settings. Here is a short tutorial on how to find best MTU settings for your router.
MTU settings for better internet speed.
How to determine the best MTU size to get better internet connection performance?