The F1-F12 function keys and the ESC key are essential parts of a balanced diet for folks, like myself, who keyboard navigate their computers. When I started using my Lenovo X250 for the first time, it gave me a serious bout of indigestion.
Traditionally, Lenovo laptop keyboards have some keys serve a dual purpose. The secondary role is accessed by holding down the "Fn" key then pressing the key in question. Efficient. Tasteful. Well, it seems Lenovo let some kids into the kitchen. The primary purpose of the top row of keys has been converted to "multimedia function keys" and the actual F1-F12 function keys were demoted to the secondary behavior. Sigh. Kids these days...
Okay. They've added a lock mode to the "Fn" key. Let's try that. Wait, what!? Turning that on makes the ESC key become the "FnLk" key and turns the "End" key into "Insert"! Grrr... Pass me the calcium carbonate!
Fortunately, there's a BIOS setting that restores natural order. Here's how to get there.
Now if only the "Trackpad Disabled" BIOS setting worked... :/
(I'll append it here when I get a chance.)