my entire itunes setup is too too gigantic. I don't know what happened. I keep getting asked to start itunes out of compatibility mode or something like that...I don't know what that means. Also, itunes store will not connect to the internet.

My entire itunes everything has become too too gigantic and I don't know why. Also, the itunes store will no longer connect to the internet. The rest of my computer connects to the internet....I actually have wireless but itunes store just stopped one day. I follow the directions posted in the help section but I fear I may be beyond help. Is there anything I can do or try??