Deane,
as far as I know iOS 5.1 was available for iPad 1 too....probably not 6.1.
Maybe you missed the iOS 5.1 step so now you cannot update to the latest iOS (6.1)

there is the possibilty to install older iOS version (5.1) using iTunes,
but the explanation would be long and very OT.

if you are interested give a look with Google...
on the other side even iOS 5.1 could be too heavy for iPad1...