I'm not a fan of the built-in search in Windows 8 - sure, it's really powerful when you get to know all the search operators, but it's not all that simple, and I hate going to the Metro screen.
That's where the wonderful Everything search comes into play... the problem is that for me, at least, the Everything window won't assign to Win + F even when you set it to.
Here's what I do instead. Using AutoHotkey, I setup a very simple rule:
That re-maps Win+F to Win+Y instead. Then I go into the Everything options and change the launcher to Win + Y as the hotkey.
Now you can use Win + F to launch Everything, and use the Esc key to make it disappear (it'll live in the system tray).
You'll get the most out of Everything by heading into the options and setting up include/exclude folders. For instance, you really don't need to index the Windows folder.