How to upgrade ios 5 in ipad 2

You must use iTunes to upgrade a device running iOS4 or earlier. Follow these instructions: http://support.apple.com/kb/HT4972

Not sure whether you want to upgrade to iOS 5 or you have iOS 5 and want to upgrade from it, but you can only update to the highest iOS 6 version that a device supports, which for an iPad 2 is 6.1.3. If you already have iOS 5+ then you should have a Settings > General > Software Update option on it for direct update update on it, otherwise you can only update via your computer's iTunes.

To update via your computer, connect the iPad to your computer's iTunes and copy any purchases off the iPad to your computer via File > Devices > Transfer Purchases. You may also want to copy photosand any important documents off the iPad as well e.g. via the file sharingsection at the bottom of the device's apps tab when connected to iTunes, via wifi, email, dropbox etc - they should be included in the backup, but it's best to havea copy of them outside of the backup just in case. You can then force a backup of the iPad by right-clicking the iPad 'Device' on the left-hand sidebar of iTunes and selecting 'Backup' (on iTunes 11 you can enable the left-hand sidebar via option-command-S on a Mac, control-S on a PC)

Then start the update by selecting the iPad on the left-hand sidebar, and on the Summary tab on the right-hand side clicking the Check For Updates button

Updating to iOS 5+ : http://support.apple.com/kb/HT4972

If you have an iPad 1, the max iOS is 5.1.1. For newer iPads, the current iOS is 6.1.3. The Settings>General>Software Update only appears if you have iOS 5.0 or higher currently installed.

iOS 5: Updating your device to iOS 5 or Later

http://support.apple.com/kb/HT4972

How to install iOS 6

http://www.macworld.com/article/2010061/hands-on-with-ios-6-installation.html

iOS: How to update your iPhone, iPad, or iPod touch

http://support.apple.com/kb/HT4623

If you are currently running an iOS lower than 5.0, connect the iPad to the computer, open iTunes. Then select the iPad under the Devices heading on the left, click on the Summary tab and then click on Check for Update.

Tip - If connected to your computer, you may need to disable your firewall and anitvirus software temporarily. Then download and install the iOS update. Be sure and backup your iPad before the iOS update. After you update an iPad (except iPad 1) to iOS 6.x, the next update can be installed via wifi (i.e., not connected to your computer).

Tip 2 - If you're updating via wifi, place your iPad close to your router to preclude getting a corrupted download.

 Cheers, Tom 😉