How much damage does this blue lightening do anyway? Vader takes a face shot before he tosses the emperor... light sabers can block it as exhibited in the emperor/Windu duel. It obviously was enough to finish off Vader... Luke could take a certain amount of it, I guess. Unless you're thinking is that the emperor was taking it easy on luke.
I think Windu could indeed take the emperor. It seems to me I remember a story about Mace having not only Jedi training, but Sith training as well. Don't get all over my case because I can't remember where I got the story.. But I do remember talking about it one time. It might be in the books somewhere.. or it might be some idiot sprouting crap on some forum... but the discussion was something along the lines of Mace's light saber color... and how it's purple, red and blue, or Jedi and sith Kaiburr crystal colors... blah, blah, blah. I think the story follows this thinking well. I think his Sith Training would have convinced him that the courts would only work in Palpatine's favor.. and killing him then was the answer, irregardless of Jedi training. I think Windu is more powerful then the movies let on. And I'm no fan of Windu... Well.. let me rephrase that.. Maybe not so much Windu.. as Samuel Jackson's acting in the part.