iphone 4s did not work after trying to upgrade from ios 5 to ios 6 unsuccessfully my iphone 4s was with ios 5.0 and already jailbreak when purchased,  I just tried to upgrade it to 6.13, on it own (which is I did not hook up my iphone with my computer nor iTunes at that time),

After a while, my iphone screen asks me to connect my iphone to iTunes, so I connect it to my computer, but then, the worst thing happened>>  ITunes says it detected my iphone is in recovery mode, and I must restore my iphone to its original setting before it can be used with iTunes.

It is a nightmare, I don't want to lose all my data, messages, pics.

Can anyone help?  Many thanks.
Have you already tried to kick off your iPhone from recovery mode? This could be done with programs such as Tiny Umbrella or ReiBoot.