The 'Google Windows popping open' is the clue - you've been infected by a trojan. You should seek help from someone you know and trust who can identify the trojan and fix the problem for you.

I somehow doubt that you'll be able to use System Restore, because trojans usually disable such things.

However, try switching off the computer in the normal way, then switching back on, tapping the F8 key until you see a list of startup options.

The option you want is 'Safe Mode'. Once safe mode is started, you'll get the option to continue working in safe mode (not a lot of use to you) or selecting a restore point as Bill suggested.

If you are asked for an administrator's password, then you cannot use system restore because of the infection. If, however, it does let you choose a restore point, make sure that as soon as you are up and running again that you download and install Microsoft Security Essentials (be sure it's the genuine article) and do a full system scan.