Hi,
The BIOS settings on the screen are pretty much active as soon as you hit apply. To the left side, you will see what the values are when saved. Start off at stock speeds, then click the setting to "On", move the slider, click "Apply" .... then you will see the valeus on the left side info panel reflect your new settigns.
If it freezes, then your overclocking settings are not stable. When that happens I just hit the power or reset buttons on the motherboard.
The other thing that confuses things with Haswell is that its a CPU designed to run at minimal power/usage dependent on the power profile you've selected in Windows. It will always say i5-4670K @3.4Ghz when you right-click the properties on "My Computer" (I'm use to Core Quads reading @ the overclocked speed). To see that your overclocking is successful in Windows, you will need to download CPU-Z which shows actual clock speeds and change your power profile in Windows. Even on "Balanced" or "High Performance", you may want to whack the "Minimum CPU" to 100%.
-Weazle