Juan,

At the minimum manual 5 well help you get a grip on things.  But as I have always told pilots who were transitioning to a new aircraft, “Read everything you can about your new aircraft it will only make things easier on you.” ;)

Yes, you can fly with out the FMC but I wouldn’t.  The FMC does more than navigate for you it provides you with safe takeoff and approaches speeds, trim settings, and allows you to use the automated flight systems.

Once you have mastered programming your FMC it will become a natural part of your flight routine and won’t take that long to do. 8-)