Some growing minority of iPad 2 users are experiencing some major issues with iOS 9, this isn't affecting every older iPad 2 user.
The only way to know if you should update to iOS 9.2 is to gauge how your iPad 2 is currently running with iOS 9.1.
If your iPad 2 is running alright on 9.1, it should continue to run alright running iOS 9.2.
If your iPad 2 is having ANY difficulties with the current iOS 9.1, then you may want to assess these issues before deciding to continue to update to the latest iOS version.
Best and most reliable method for upgrading/updating an iDevice to the latest iOS version.
How much free storage space is left on all of your iDevices.Ideally, your iDevice should maintain a minimum free storage amount of 4- 6 GBs or greater on any iDevice (the more free space, the better) , plus, more than 50%-60% battery status to ensure proper operation, as well as, to ensure the possibility of a successful iOS upgrade/update installation.In addition it is best to upgrade an iDevice connected up to a computer running iTunes with you iDevice sync'd and backed up through iTunes rather than Over The Air (OTA) using a wireless WiFi connection.I update ALL my iDevices connected up to my iMac and sync'd over USB through iTunes.I have NEVER, EVER had an issue with any iOS updates.
Here is my own restore procedure that has already worked, sucessfully, for a few iPad 2 users, so far!
I have done this and my iPad 2 and 3 are working like new, " out of the box" units!
First, connect your iPad to USB and sync and backup your iPad to iTunes (make sure your iTunes is up to date).
Then disconnect/eject your iPad from the computer.
From just the iPad, in the Settings App under the General setting, look in the right column for Reset option, then erase and reset your iPad to completely erase your iPad and then, again, from the iPad, set it up as a new iPad setup to factory "out of the box" operation.
Then reconnect your iPad to the computer and make sure to cancel the syncing, by tapping the small X to the left in the top center iTunes display box.
iTunes should detect your iPad. If iTunes begins to try and sync, again, cancel the sync.
Select Restore from Backup instead and pick your last backup to restore back to your iPad.
Once the restore is complete, finish setting up the iPad and let it sync back to iTunes you can either cancel the sync, again or let it backup, again.
Then disconnect the iPad.
Do one hard reset of your iPad by holding down both the Home and sleep/wake buttons simultaneously until your iPad goes to black and restarts with Apple logo, then release the buttons.
Once your iPad is back to the Home screen,
In the Settings App under the General tab, to the right under Spotlight sesrch, try disabling the search under apps that really do not need a search, like some games, remotes, apps that really do not need to be searched, etc., to reduce the list for Spotlight to search.
Try turning on Reduced Motion.
This is found in the Settings App in the General tab the left panel.
In the right panel look under Accessibility, the look for Reduce Motion and turn this feature "On".
You should see an appreciable performance increase on all iPad 2, 3 and 4 models.
In the Settings App under the General Tab, in the right column, look for Background App Refresh and turn this setting to "off".
If you purchased any music from iTunes, you will need to redownload that content back to your iPad for playing directly from your iPad and not from Apple Music servers.
Also, if your iPad contained a lot of images in the Photos app, these will take time to regenerate the original AND thumbnail images themselves inside of the Photos app when you first launch it.