Rhubarb

Yes, at least wait for them to yellow and wilt.   Do you have to move em ?

somebody wants a few  so yes 

Is it best to leave the fallen leaves to rot aound it or clear them up? anyone know?

I had leaves on mine about a month ago, and as they were yellowing, I tugged them off, and through them in the compost.  I didn't go on the allotment until on Saturday, and one of my jobs was to clear it all up, and found there wasn't any leaves at all.  So basically, I've left the plot alone.

If you want to give any to your friends, just dig them up, and then leave them for the frost to have a go, then plant them sometime in January/February, they'll be fine.