You gave poor, ineffective information and I gave a viable workaround to attempt. That's what a support community does, they help each other. webrosc was not at all helpful , and attempting to start a flame war is inexcusable.
Yes, I don't have a high post count because I haven't needed the support. However this issue is larger than one would think and a perfunctory search via Google would show that.
It's disarming to hear you passing off information from the people that have been helping here for years "ineffective." None of us are paid, nor are we obligated to helping users yet even so we take time into actually solving the issues that people may have.
As you are disputing the solution brought forward, you are implying that you are knowledgeable with the circumstances involved with the issue and are confident in the premise of the issue, that your solution will apply to the end user. When you encounter an issue you are given an opportunity to try and formulate a fix, but you are forgetting an important part -- that being the cause of the issue. Thinking you have a solution to something without knowing the cause will come back to you once someone has an issue that cannot be resolved by your "fix".
You bring to your defense that you used Google to gather a perfunctory conclusion that the issue was nothing more than a rendering issue that affects a user when fullscreen mode is active. When I search up "pixel format not accelerated" I get sent to the Minecraft Hopper page entailing that a driver issue is the cause, and also lists "Graphics drivers are outdated" and "Invalid memory allocation" (I'll come back to these later) as causes to the issue the OP (acronym used on forums for "original post[er]") was encountering. When you look things up you generally don't look for a cause, you look for a solution -- those solutions may not apply to everyone and you will never know unless you find the cause. In this case, the exception is being thrown by LWJGL (you can note the stack trace) due to it not being able to initiate OpenGL.
I intend to keep this simple, but I'll try to explain the issue as thoroughly as I can.
Minecraft is written in Java, which runs on the Java Virtual Machine. When you're writing Java code, you don't target the host machine but instead that virtual machine. That VM grants Java code the ability to run in any operating system so long that someone has written a VM implementation for that OS. At the same time, this prohibits Minecraft from having low-level access to components like the system's video card and thus there needs to be an intermediary that can run natively on an operating system, in this case that being LWJGL which acts as a wrapper allowing Minecraft to interface with OpenGL. So when Minecraft attempts to launch the game, it needs to load LWJGL so it can initiate OpenGL. When this call fails, you get the error as shown above and referred to as "Pixel format not accelerated" which is thrown by LWJGL as a wrapper to the native exception (sometimes LWJGL doesn't catch the exception, resulting in access violation errors). It's not the most descriptive of errors, but at the same time it wasn't written with the intention to make it descriptive. If you're getting along with this, you can see that there's a large gap of possibilities for what went wrong.
For the most part, the inability to initiate OpenGL is due to one's graphics drivers not supporting a proper implementation of OpenGL. It's common enough that Intel has an article stating that "Graphics drivers that come with Microsoft Windows* or that are downloaded from Windows Update typically do not support OpenGL" -- this is due to Intel choosing to not add OpenGL support in some of the drivers they push with Windows Update. That's why people are forwarded to getting drivers from their hardware manufacturers instead of the drivers given by Windows Update (not in all cases!). The same can also be said for AMD, who have taken part in the same issue. Recently, Microsoft released Windows 10 (yay) which just as any OS upgrade has worked, remove graphics drivers and default to the generic graphics drivers provided by Microsoft for Windows 10, however these drivers don't hardware acceleration and also not OpenGL. They basically are there to provide basic graphics functionality so Windows can function, nothing fancy. To reiterate as cestislife explained to you, Windows normally takes care of updating your drivers but in addition to what I just explained, Windows may not be able to find a proper driver at all, or the user hasn't restarted their computer to finish installing Windows Updates that contain a driver update. Read more. I find it a bit dubious that you're claiming to get PFNA errors anywhere but the initial game load, so please send the error log as well as the launcher logs and I'll look into it.
Now, you dismissed webrosc's correct advise to request a DxDiag report under the premises that DirectX is not used by Minecraft (the launcher does!). As while this is correct, it makes no difference as it gets the job done and has all the information we need. We don't need a 3rd party tool to get system information when tools like dxdiag.exe and msinfo32.exe are provided by Microsoft for this exact purpose -- getting system information concisely for debugging problems.
If you've gotten me so far, if you go back to what cestislife told you -- to reiterate the majority of users encountering this error are due to them not having drivers that support proper a proper OpenGL implementation. See the link you were given and it should explain to you how to go about helping people update their drivers.
My apologies if this may sound a bit provocative, I'm posting this not only as a response to your claim that "the advice we're giving is not helpful" but also as a reference for others that may come across this post.
If you have any further questions about the technical background on the issue, you should ask on the gamedev StackExchange here (or the off-topic section here even?) instead of replying here.
Looking at the Dxdiag log, you have switchable graphics. You're using the ASUS GR6, yes?
If so, the previous driver link only solved half the issue. Basically, your computer has two graphics cards. Intel Intergrated, and an NVIDIA card. You should have the driver for the Intel card now, but not the NVIDIA card. You can download the drivers you need from the driver download page for your computer HERE.
Once you click the link, click the arrow next to "VGA" and download both the drivers from the links. The Intel one you should install first, then the NVIDIA one.
If the installer for the Intel graphics says you're already up to date, that's fine. Just go install the NVIDIA drivers. Once you do this, reboot and (in theory) you should be able to play, though I'm not sure how you'd go about actually having Windows 10 switch to the NVIDIA card... I'm sure someone else here knows