Just download and install FireFox and import your favourites from IE, make sure you study all the options offered and untick anything you don't want such as yahoo search box or whatever it's called.
As for I-google home page problem I suggest you download and run CC cleaner in the registry clean mode. I'm assuming you've tried resetting your home page from the 'tools>options' menu. If you run it in the 'cleaner mode' use the cookie option in options so as not to delete cookies from sites you auto-log into.
Edit Milo posted as I was typing