I would say it is a Tallow tree based on the pics. The leaf (tallowtree_01) looks exactly like the illustration in Dirr's Manual of Woody Landscape Plants. I have never seen one of theses in person. They are interesting! Looks like it is noted as an invasive species as well: http://www.invasivespeciesinfo.gov/p...intallow.shtml
1.) definitely chinese tallow
2.) Are there two different trees shown in the pictures? Look up laurel oak (quercus laurifolia), southern red oak (quercus falcata) and blackjack oak and see if those match.
3.) I don't know.
4.) Looks like Chinaberry unfortunately
5.) Red mulberry would be my best guess with the limited information provided.
Tree 3.... could it be some kind of ficus (fig) tree? Given the location leaf shape, texture and petiole length this would be my best guess. Might be a shortleaf fig. Did this tree appear to be growing around another tree? It could be a strangler fig. Here is a link to a long list of trees common to south FL.