[Nook HD, HD+ Q&A, Help & Troubleshooting] HiddenG:
OOBE, known as Out-of-Box-Experience. Basically after registering, you get the experience you should. Skipping OOBE is basically not registering the product, and entering a development/test mode. OOBE is associated with not registering the device.

The Nook HD+ requires a WiFi connection to register the product, and what if the end-user doesn't have WiFi? I guess that's tough on them, they can't register. To be honest, I can't believe it either. To use the HD+ if you do not have WiFi, is to skip OOBE (which is the same procedure as the Nook Color's).

If you skip OOBE, then there is nothing to play with on the tablet; other than familiarising yourself with the interface. That's it. Not even the browser works; actually it has no apps at all. If you later root the tablet [and install GAPPs], whilst not registering the tablet, you will eventually get a lot more features; and pretty much use it like any other Android tablet. However, a lot of features will be disabled, such as the stock Android Browser (it will not load, as it will not be installed). A lot of other apps may then cause problems, due to the default browser not being present (i.e. BBC iPlayer). With the All in One root, developed by someone0, it will disable automatic OTA updates, so you will not update any further than your current factory version. However, some users (including myself) have been forced the update, so you cannot be certain that you will remain on the factory version (those prior to 2.0.5).

However, I would recommend you reconsider your options. If you want a better experience, I would recommend that you register the device (do NOT register now, please read the rest of my post). Important, remember the credentials you register the device with. If there are any future updates for the Nook, you will need to input the same e-mail address and password (unless password changed). If you create another B&N account at this stage, your Nook will constantly output an error; I contacted B&N today, and they couldn't solve it either. I found the solution, you have to remember the exact e-mail address you used to register. So, remember the e-mail address you use to register; and absolutely the password too, or the security question. Without them, you will not be able to register your device again.

Continuing on, I stated I would recommend you to register the device. However, before you do so, please make sure you have a minimum 4GB microSD card present (I used a SanDisk 4GB class 4). When you register your device, your Nook will check for updates. It will find 2.0.5 and update to it. Just so you know, someone0 and leapinlar have worked together to bring a "Universal Root" for the Nook HD+ and that universal root even roots version 2.0.5 (thank you someone0 and leapinlar; I'm currently using it). After registering your device, you will be introduced to your Nook interface. It's empty, even the apps are pretty much useless (except for Browser, only positive); you can't even spend more than 10 minutes on it, without enjoying what your doing. So I would recommend the root + GAPPs to unlock most of the "Android" features. To use the universal root, you'll need to boot into CWM (ClockWorkMod) via SD card (minimum of 4GB, anything less won't be detected/viable). Before registering and continuing with what I say, please make sure you are able to write onto your SD card using your computer. Although we are using CWM, we are NOT going to flash any ROMs (unless you want to of course, but the following "guide" below won't detail so).

First, you'll need to insert your SD card into your computer; where you're in a position where you can write on the card. (Files links/sources/information was sourced from http://xdaforums.com/showthread.php?t=2062613)

Write the CWM .img (NookHD+bootable-CWM-6023-for-emmc-stock-4GB.zip) onto the SD Card using "Win32diskimager in Windows or use the dd command in Linux or OSX".

Download NookHD+Universal-Root.zip and place it within the SD Card. Also do this for the GAPPS + EXTRAS (including ManualOTA and Unknown Sources) .zip file, which you can download here (put together by leapinlar). DO NOT extract the .zip, just place them into the SD card.

At this point, make sure you have registered your Nook HD+, updated and installed version 2.0.5. Also make sure you have launched the stock ROM at least once (i.e. turned on the device into the Nook software/modified Android OS).

Now, turn off your device (hold the power button until a message is displayed on screen, and press shut down, or similar on screen). At the bottom of the Nook, on the left of the charging port, there is a cover protecting the SD card slot. Take it out (not all the way, it's attached to the body), and place in your SD card (with the CWM and universal root, as well optionally the GAPPS; although recommend installed on the SD card).

With the SD card in, turn your Nook on. After a few seconds, you should load into CWM. Select the option "install .zip from SD card" (use volume up/down to move across the list, "n" button below screen to select, and power button to move up one menu).

Firstly, install "NookHD+Universal-Root.zip". Wait for it to fully install, then install the GAPPS + Extras.

After the last step, reboot your device and take out the SD card before reboot. You should now load into your stock OS, whilst being rooted and and GAPPs installed on version 2.0.5. Success!

After the above guide, I would personally recommend Nova Launcher Prime; it unleashes the full experience of Android for me anyway. Haha, from now it's all yours. :)

That should be all from me, and the best of luck. I support you either way, whether you register or not. Merry Christmas too by the way. :)