If you cannot get to the forums, or are having trouble getting to the main WEB page, there is a good chance you will not be able to maintain a connection to the game servers either.
When this happens, you need to run a Ping Plot to see where the failure is. If your ISP is using Level3 as its Tier 1 transport, the problems you describe would not surprise me.
Surfing the WEB is very different from playing a real-time game over the Internet. "Pardon me while I stop your plane in the air until we can finally get that packet of data to your computer", does not work so well.