I think your question's much too open-ended to give it a considered answer. Do you have any lens adapters already? Do you like to get the camera in the middle of the action with a wide-angle lens, or prefer the camera as a voyeur, on a telephoto lens from far away?
If you have a brilliant choreographer, it could be great to imitate some of the Asian martial arts films and let the whole fight play out on a wide master. In recent years, Hollywood has often gone for much tighter shots with faster cuts, which can work to great effect (as I believe it did in the Bourne films) but often seems to be used out of laziness more than anything else.
The academic David Bordwell has written a great essay on these two significantly different approaches - Bond vs. Chan. I'd recommend reading this and thinking about how you want your fight scene to play out before getting too involved in the technical details.