Newbie here. I've decided that I want to update to iOS 5.1. I can wait for a jailbreak.
I do use a lot of tweaks but I would like to return to stock for now. I tried to just download the update
Over air but after downloading I receive an error massage when it try's to install.
Do I just need to update from iTunes? Thanks for any help.

To remove your jailbreak and install 5.1 you need to use the complete restore on iTunes.

The way the jailbreak works on the ipad 2 means system files need to be modified, moved, renamed, etc. and usually will cause an iOS update to fail. In the even it does update it can cause a multitude of problems, especially when rebooting the device because of the files needed to run an untethered jailbreak tend to be where stock iOS files are.

Because of this you need to actually restore it in iTunes because that will replace all the files in the system portion of the iPad with the factory specified ones.

Spacegoogie - Have a look at this thread here: TUTORIAL - Failsafe method to restore the current version of IOS

It's been pretty effective in the past in getting folks' iPads restored to the latest firmware.

Good luck and let us know how you get on.

Marilyn