Thanks for everyone that sacrificed a bit of their time to help me
I got my F-buttons working again after my internet was off for 3 hrs.
Especially thanks to BaranCODE!

Allrightey, thanks for all the tips!

Hey I have windows 8 and i did have that problem shift + f1/f2 ect

Hope i helped

~Goofy

I'm also a Windows 8 user, and I have the same problem. On my laptop (HP Pavilion G7) you can simply hold shift and press the F key. For example, pressing F11 normally will turn off the sound. Holding shift and pressing it causes it to put MInecraft into fullscreen. Hope I helped.

I use win8 and f- buttons work for me

Press the F11 thing again, once or twice, it should bring it back to the normal mode. (If it doesn't work, restart computer, that should certainly work.)

See the blue signs on the buttons? Those are supposed to work only when you are pressing FN (because it is blue). But apparently, they work without pressing FN. I know of computers that can do this, and FN has the opposite effect (it triggers the non-blue signs). But you said the F-buttons don't work when pressing the FN either, so I don't have any idea.
Is it possible the FN button is stuck or something? Cause sometimes the answer to our problems is much simpler than we think.
I don't have any other ideas, sorry.

Also, once I tried the F11 thing my computer has started lagging ALOT!

Allright here's the link
http://s1274.photobucket.com/user/ROPRO ... sort=3&o=0
Hope it helps

Could you attach a photo of your keyboard? That would help.

Try the F11 in Internet Explorer thing again, but do it while pressing FN, Alt, CTRL, etc. (one by one, not at the same time)

Umm... Any information of how I can set them back?

I also have Win8.
The reason that made your laptop loud is probably because it changed the power of the cooling fan. What I'm assuming is that your F-buttons are currently set to be FN-buttons or similar as default. You need to find the key (FN, Alt, etc.) that uses those F-buttons as F-buttons.
I have experienced the same situation, so I know firsthand.

IVE GOT WINDOWS 8. SO YOU CAN TRUST ME..

Just press CTRL (Left Side) or ALT or FM also you could press ALT GR and
CTRL (Right side)

Thank you and i hoped this helped

~Social

No, it just makes my laptop loud as hell

As far as I know, making the screen dimmer and brighter aren't the functions of the F-Buttons, but the FN-buttons.
For example, try pressing F11 in Internet Explorer. Does it go fullscreen?

I use the F button and shift at the same time it works for me and i use windows
I dont know if it will work for you, but i hope it does!

Dude this feature were removed in 1.7 or something like that.

Do they work outside of minecraft?