I'm sorry, I know the post is too old, but I got the same problem. iTunes installed iCloud in my desktop (WIN 7), and everytime I opened my "contacts" it was open it in IE. I was looking for the main command or Default command. The way I solved this issue is as follow.
1.) in the start menu, write "Internet Options"
2.) in General> Home Page>to create home page tabs:paste the main page you want to use as your Browser" in this case Google Exp:/https://www.google.com/
click in "APPLY, (botton Bottom) and clos this window
3.) Open your browser and GO Settings> and select your Browser default.
......And that's ALL.
😮I do not understand why some people they don't know anything about it keep asking questions, if they don't know how to solve the problem??
I hope this can help somebody else.😉