Favorite Byzantine Emperor(dates of reign in parenthesis)

I'd have to go with Justinian largely because of his efforts in rebuilding the Roman empire and how his general Belisarus was able to return the favor to the Vandals (who sacked Rome under their king Genseric and were able to maintain control of Carthage throughout his reign).  Though ultimately doomed, he did surround himself with people like Belisarus that achieved much of what he wanted.

Yes, Justinian weakened and overextended the state so much, that in nearly fell to the Persian in the next generation... until Heraclius rose and saved the empire.

Heraclius is a great omission in your list, btw. I settled with Basil II, as he was even more succesful. The other really succesful Byzantine Emperor was Alexios I Comnenus and in such a poll I would be obliged to include the names of John Comnenus and Nicephorus Phokas.

I have voted to Justinian I, to some people his reign was terrible for the Empire, but it was a golden age thanks to Belisarius 

Woops! I didn't see the other poll on this exact same thing.